Auto merge of #11239 - jdm:time-profile, r=nox

Add timeline markers for HTTP requests, JS evaluation, and HTML parsing.

Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `__` with appropriate data:
- [ ] `./mach build -d` does not report any errors (didn't try to compile past a rustc upgrade on airplane wifi)
- [X] `./mach test-tidy --faster` does not report any errors
- [X] These changes fix #11218 (github issue number if applicable).

Either:
- [ ] There are tests for these changes OR
- [X] These changes do not require tests because we don't have testing infrastructure for profiling.

Pull requests that do not address these steps are welcome, but they will require additional verification as part of the review process.

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components/script/dom/window.rs

@@ -51,6 +51,8 @@ use net_traits::image_cache_thread::{ImageCacheChan, ImageCacheThread};
 use net_traits::storage_thread::{StorageThread, StorageType};
 use num_traits::ToPrimitive;
 use profile_traits::mem;
+use profile_traits::time::{ProfilerCategory, TimerMetadata, TimerMetadataFrameType};
+use profile_traits::time::{ProfilerChan, TimerMetadataReflowType, profile};
 use reporter::CSSErrorReporter;
 use rustc_serialize::base64::{FromBase64, STANDARD, ToBase64};
 use script_runtime::{ScriptChan, ScriptPort};
@@ -165,6 +167,10 @@ pub struct Window {
     #[ignore_heap_size_of = "channels are hard"]
     mem_profiler_chan: mem::ProfilerChan,
 
+    /// For sending messages to the memory profiler.
+    #[ignore_heap_size_of = "channels are hard"]
+    time_profiler_chan: ProfilerChan,
+
     /// For providing instructions to an optional devtools server.
     #[ignore_heap_size_of = "channels are hard"]
     devtools_chan: Option<IpcSender<ScriptToDevtoolsControlMsg>>,
@@ -844,21 +850,37 @@ impl<'a, T: Reflectable> ScriptHelpers for &'a T {
     fn evaluate_script_on_global_with_result(self, code: &str, filename: &str,
                                              rval: MutableHandleValue) {
         let global = self.global();
-        let cx = global.r().get_cx();
-        let globalhandle = global.r().reflector().get_jsobject();
-        let code: Vec<u16> = code.encode_utf16().collect();
-        let filename = CString::new(filename).unwrap();
+        let metadata = TimerMetadata {
+            url: if filename.is_empty() {
+                global.r().get_url().as_str().into()
+            } else {
+                filename.into()
+            },
+            iframe: TimerMetadataFrameType::RootWindow,
+            incremental: TimerMetadataReflowType::FirstReflow,
+        };
+        profile(
+            ProfilerCategory::ScriptEvaluate,
+            Some(metadata),
+            global.r().time_profiler_chan().clone(),
+            || {
+                let cx = global.r().get_cx();
+                let globalhandle = global.r().reflector().get_jsobject();
+                let code: Vec<u16> = code.encode_utf16().collect();
+                let filename = CString::new(filename).unwrap();
 
-        let _ac = JSAutoCompartment::new(cx, globalhandle.get());
-        let options = CompileOptionsWrapper::new(cx, filename.as_ptr(), 0);
-        unsafe {
-            if !Evaluate2(cx, options.ptr, code.as_ptr(),
-                          code.len() as libc::size_t,
-                          rval) {
-                debug!("error evaluating JS string");
-                report_pending_exception(cx, globalhandle.get());
+                let _ac = JSAutoCompartment::new(cx, globalhandle.get());
+                let options = CompileOptionsWrapper::new(cx, filename.as_ptr(), 0);
+                unsafe {
+                    if !Evaluate2(cx, options.ptr, code.as_ptr(),
+                                  code.len() as libc::size_t,
+                                  rval) {
+                        debug!("error evaluating JS string");
+                        report_pending_exception(cx, globalhandle.get());
+                    }
+                }
             }
-        }
+        )
     }
 }
 
@@ -1262,6 +1284,10 @@ impl Window {
         &self.mem_profiler_chan
     }
 
+    pub fn time_profiler_chan(&self) -> &ProfilerChan {
+        &self.time_profiler_chan
+    }
+
     pub fn devtools_chan(&self) -> Option<IpcSender<ScriptToDevtoolsControlMsg>> {
         self.devtools_chan.clone()
     }
@@ -1431,6 +1457,7 @@ impl Window {
                bluetooth_thread: IpcSender<BluetoothMethodMsg>,
                storage_thread: StorageThread,
                mem_profiler_chan: mem::ProfilerChan,
+               time_profiler_chan: ProfilerChan,
                devtools_chan: Option<IpcSender<ScriptToDevtoolsControlMsg>>,
                constellation_chan: ConstellationChan<ConstellationMsg>,
                control_chan: IpcSender<ConstellationControlMsg>,
@@ -1468,6 +1495,7 @@ impl Window {
             navigator: Default::default(),
             image_cache_thread: image_cache_thread,
             mem_profiler_chan: mem_profiler_chan,
+            time_profiler_chan: time_profiler_chan,
             devtools_chan: devtools_chan,
             browsing_context: Default::default(),
             performance: Default::default(),