ports/cef: Use the CEF translator tool to generate the full set of CEF

bindings.

This replaces hand-implemented CEF bindings with proper Rust wrappers
automatically generated from the C++ headers. This means that, whenever
CEF's C++ headers change, we can easily generate both the appropriate C
API and the appropriate Rust API. It eliminates much of the hand-written
unsafe code within the CEF port, because the CEF translator tool now
knows how to generate Rust smart pointer wrappers for each class that
corrently perform reference counting.

Additionally, this commit adds utility macros (located in `macros.rs`)
that make it easier to correctly expose Rust objects as CEF objects.
They handle the marshaling of objects between Rust and CEF properly.
The net result of this is that you can write mostly-natural-looking Rust
in the CEF port and interact with it with a natural-looking C++ API on
the embedding side.

This setup relies on the branch of CEF located here:

    https://github.com/pcwalton/chromium-embedded-framework

To regenerate, follow the instructions in `ports/cef/README.md`. For
convenience, and because I don't anticipate the API to change much, I
have vendored in all of the appropriate interfaces.

ports/cef/interfaces/cef_resource_bundle_handler.rs

@@ -0,0 +1,231 @@
+// Copyright (c) 2014 Marshall A. Greenblatt. All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//    * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//    * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//    * Neither the name of Google Inc. nor the name Chromium Embedded
+// Framework nor the names of its contributors may be used to endorse
+// or promote products derived from this software without specific prior
+// written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+//
+// ---------------------------------------------------------------------------
+//
+// This file was generated by the CEF translator tool and should not be edited
+// by hand. See the translator.README.txt file in the tools directory for
+// more information.
+//
+
+#![allow(non_snake_case, unused_imports)]
+
+use eutil;
+use interfaces;
+use types;
+use wrappers::CefWrap;
+
+use libc;
+use std::collections::HashMap;
+use std::ptr;
+
+//
+// Structure used to implement a custom resource bundle structure. The functions
+// of this structure may be called on multiple threads.
+//
+#[repr(C)]
+pub struct _cef_resource_bundle_handler_t {
+  //
+  // Base structure.
+  //
+  pub base: types::cef_base_t,
+
+  //
+  // Called to retrieve a localized translation for the string specified by
+  // |message_id|. To provide the translation set |string| to the translation
+  // string and return true (1). To use the default translation return false
+  // (0). Supported message IDs are listed in cef_pack_strings.h.
+  //
+  pub get_localized_string: Option<extern "C" fn(
+      this: *mut cef_resource_bundle_handler_t, message_id: libc::c_int,
+      string: *mut types::cef_string_t) -> libc::c_int>,
+
+  //
+  // Called to retrieve data for the resource specified by |resource_id|. To
+  // provide the resource data set |data| and |data_size| to the data pointer
+  // and size respectively and return true (1). To use the default resource data
+  // return false (0). The resource data will not be copied and must remain
+  // resident in memory. Supported resource IDs are listed in
+  // cef_pack_resources.h.
+  //
+  pub get_data_resource: Option<extern "C" fn(
+      this: *mut cef_resource_bundle_handler_t, resource_id: libc::c_int,
+      data: *mut *mut libc::c_void,
+      data_size: *mut libc::size_t) -> libc::c_int>,
+
+  //
+  // The reference count. This will only be present for Rust instances!
+  //
+  ref_count: uint,
+
+  //
+  // Extra data. This will only be present for Rust instances!
+  //
+  pub extra: u8,
+} 
+
+pub type cef_resource_bundle_handler_t = _cef_resource_bundle_handler_t;
+
+
+//
+// Structure used to implement a custom resource bundle structure. The functions
+// of this structure may be called on multiple threads.
+//
+pub struct CefResourceBundleHandler {
+  c_object: *mut cef_resource_bundle_handler_t,
+}
+
+impl Clone for CefResourceBundleHandler {
+  fn clone(&self) -> CefResourceBundleHandler{
+    unsafe {
+      if !self.c_object.is_null() {
+        ((*self.c_object).base.add_ref.unwrap())(&mut (*self.c_object).base);
+      }
+      CefResourceBundleHandler {
+        c_object: self.c_object,
+      }
+    }
+  }
+}
+
+impl Drop for CefResourceBundleHandler {
+  fn drop(&mut self) {
+    unsafe {
+      if !self.c_object.is_null() {
+        ((*self.c_object).base.release.unwrap())(&mut (*self.c_object).base);
+      }
+    }
+  }
+}
+
+impl CefResourceBundleHandler {
+  pub unsafe fn from_c_object(c_object: *mut cef_resource_bundle_handler_t) -> CefResourceBundleHandler {
+    CefResourceBundleHandler {
+      c_object: c_object,
+    }
+  }
+
+  pub unsafe fn from_c_object_addref(c_object: *mut cef_resource_bundle_handler_t) -> CefResourceBundleHandler {
+    if !c_object.is_null() {
+      ((*c_object).base.add_ref.unwrap())(&mut (*c_object).base);
+    }
+    CefResourceBundleHandler {
+      c_object: c_object,
+    }
+  }
+
+  pub fn c_object(&self) -> *mut cef_resource_bundle_handler_t {
+    self.c_object
+  }
+
+  pub fn c_object_addrefed(&self) -> *mut cef_resource_bundle_handler_t {
+    unsafe {
+      if !self.c_object.is_null() {
+        eutil::add_ref(self.c_object as *mut types::cef_base_t);
+      }
+      self.c_object
+    }
+  }
+
+  pub fn is_null_cef_object(&self) -> bool {
+    self.c_object.is_null()
+  }
+  pub fn is_not_null_cef_object(&self) -> bool {
+    !self.c_object.is_null()
+  }
+
+  //
+  // Called to retrieve a localized translation for the string specified by
+  // |message_id|. To provide the translation set |string| to the translation
+  // string and return true (1). To use the default translation return false
+  // (0). Supported message IDs are listed in cef_pack_strings.h.
+  //
+  pub fn get_localized_string(&self, message_id: libc::c_int,
+      string: *mut types::cef_string_t) -> libc::c_int {
+    if self.c_object.is_null() {
+      panic!("called a CEF method on a null object")
+    }
+    unsafe {
+      CefWrap::to_rust(
+        ((*self.c_object).get_localized_string.unwrap())(
+          self.c_object,
+          CefWrap::to_c(message_id),
+          CefWrap::to_c(string)))
+    }
+  }
+
+  //
+  // Called to retrieve data for the resource specified by |resource_id|. To
+  // provide the resource data set |data| and |data_size| to the data pointer
+  // and size respectively and return true (1). To use the default resource data
+  // return false (0). The resource data will not be copied and must remain
+  // resident in memory. Supported resource IDs are listed in
+  // cef_pack_resources.h.
+  //
+  pub fn get_data_resource(&self, resource_id: libc::c_int,
+      data: &mut *mut libc::c_void,
+      data_size: &mut libc::size_t) -> libc::c_int {
+    if self.c_object.is_null() {
+      panic!("called a CEF method on a null object")
+    }
+    unsafe {
+      CefWrap::to_rust(
+        ((*self.c_object).get_data_resource.unwrap())(
+          self.c_object,
+          CefWrap::to_c(resource_id),
+          CefWrap::to_c(data),
+          CefWrap::to_c(data_size)))
+    }
+  }
+} 
+
+impl CefWrap<*mut cef_resource_bundle_handler_t> for CefResourceBundleHandler {
+  fn to_c(rust_object: CefResourceBundleHandler) -> *mut cef_resource_bundle_handler_t {
+    rust_object.c_object_addrefed()
+  }
+  unsafe fn to_rust(c_object: *mut cef_resource_bundle_handler_t) -> CefResourceBundleHandler {
+    CefResourceBundleHandler::from_c_object_addref(c_object)
+  }
+}
+impl CefWrap<*mut cef_resource_bundle_handler_t> for Option<CefResourceBundleHandler> {
+  fn to_c(rust_object: Option<CefResourceBundleHandler>) -> *mut cef_resource_bundle_handler_t {
+    match rust_object {
+      None => ptr::null_mut(),
+      Some(rust_object) => rust_object.c_object_addrefed(),
+    }
+  }
+  unsafe fn to_rust(c_object: *mut cef_resource_bundle_handler_t) -> Option<CefResourceBundleHandler> {
+    if c_object.is_null() {
+      None
+    } else {
+      Some(CefResourceBundleHandler::from_c_object_addref(c_object))
+    }
+  }
+}
+