Support multiple WebIDL interfaces being generated in the same output binding file.

Each interface gets its own module named ${Interface}Binding. Structs, enums, and callbacks
continue to use the root module of the binding file. If there is only one interface in the
file, we generate reexports for several public APIs and types so that existing DOM implementations
don't need any modifications. When multiple interfaces exist, the reexported names get the interface
name prepended (eg. FooWrap instead of Wrap).

As part of this work, stop glob-importing all DOM types in every generated binding and start generating
more targeted lists of relevant types based on the methods, members, etc. of WebIDL types that are in use.

components/script/dom/bindings/codegen/Configuration.py

@@ -4,7 +4,7 @@
 
 import os
 
-from WebIDL import IDLExternalInterface, IDLInterface, WebIDLError
+from WebIDL import IDLExternalInterface, IDLInterface, IDLWrapperType, WebIDLError
 
 
 class Configuration:
@@ -183,7 +183,8 @@ class Descriptor(DescriptorProvider):
         # built-in rooting mechanisms for them.
         if self.interface.isCallback():
             self.needsRooting = False
-            ty = "%sBinding::%s" % (ifaceName, ifaceName)
+            ty = 'dom::bindings::codegen::Bindings::%sBinding::%s' % (ifaceName, ifaceName)
+            pathDefault = ty
             self.returnType = "Rc<%s>" % ty
             self.argumentType = "???"
             self.nativeType = ty
@@ -192,10 +193,12 @@ class Descriptor(DescriptorProvider):
             self.returnType = "Root<%s>" % typeName
             self.argumentType = "&%s" % typeName
             self.nativeType = "*const %s" % typeName
+            pathDefault = 'dom::types::%s' % typeName
 
         self.concreteType = typeName
         self.register = desc.get('register', True)
-        self.path = desc.get('path', 'dom::types::%s' % typeName)
+        self.path = desc.get('path', pathDefault)
+        self.bindingPath = 'dom::bindings::codegen::Bindings::%s' % ('::'.join([ifaceName + 'Binding'] * 2))
         self.outerObjectHook = desc.get('outerObjectHook', 'None')
         self.proxy = False
         self.weakReferenceable = desc.get('weakReferenceable', False)
@@ -377,7 +380,8 @@ class Descriptor(DescriptorProvider):
 
 # Some utility methods
 def getModuleFromObject(object):
-    return os.path.basename(object.location.filename()).split('.webidl')[0] + 'Binding'
+    return ('dom::bindings::codegen::Bindings::' +
+            os.path.basename(object.location.filename()).split('.webidl')[0] + 'Binding')
 
 
 def getTypesFromDescriptor(descriptor):
@@ -404,6 +408,8 @@ def getTypesFromDictionary(dictionary):
     """
     Get all member types for this dictionary
     """
+    if isinstance(dictionary, IDLWrapperType):
+        dictionary = dictionary.inner
     types = []
     curDict = dictionary
     while curDict: