Auto merge of #20132 - nakul02:issue_19223, r=jdm

Profiler for blocked IpcReceiver::recv()

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Implements feature #19223

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- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix #19223 (github issue number if applicable).

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- [x] There are tests for these changes

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WIP.
@jdm - this is the new profiler : "Blocked at IPC Receive"
Should I dig through all the calls to `ipc::channel` and replace them with this profiled `IpcReceiver`?

![screenshot from 2018-02-27 01-35-37](https://user-images.githubusercontent.com/5394361/36721061-b46edea4-1b5e-11e8-91d6-7faba742f237.png)

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1 files changed, 6 insertions, 5 deletions

diff --git a/components/script/dom/canvasrenderingcontext2d.rs b/components/script/dom/canvasrenderingcontext2d.rs
index 1e2278e81ca..a837fc02fd7 100644
--- a/components/script/dom/canvasrenderingcontext2d.rs
+++ b/components/script/dom/canvasrenderingcontext2d.rs
@@ -32,7 +32,7 @@ use dom::imagedata::ImageData;
 use dom::node::{Node, NodeDamage, window_from_node};
 use dom_struct::dom_struct;
 use euclid::{Transform2D, Point2D, Vector2D, Rect, Size2D, vec2};
-use ipc_channel::ipc::{self, IpcSender};
+use ipc_channel::ipc::IpcSender;
 use net_traits::image::base::PixelFormat;
 use net_traits::image_cache::CanRequestImages;
 use net_traits::image_cache::ImageCache;
@@ -41,6 +41,7 @@ use net_traits::image_cache::ImageResponse;
 use net_traits::image_cache::ImageState;
 use net_traits::image_cache::UsePlaceholder;
 use num_traits::ToPrimitive;
+use profile_traits::ipc;
 use script_traits::ScriptMsg;
 use servo_url::ServoUrl;
 use std::{cmp, fmt, mem};
@@ -128,7 +129,7 @@ impl CanvasRenderingContext2D {
                          size: Size2D<i32>)
                          -> CanvasRenderingContext2D {
         debug!("Creating new canvas rendering context.");
-        let (sender, receiver) = ipc::channel().unwrap();
+        let (sender, receiver) = ipc::channel(global.time_profiler_chan().clone()).unwrap();
         let script_to_constellation_chan = global.script_to_constellation_chan();
         debug!("Asking constellation to create new canvas thread.");
         script_to_constellation_chan.send(ScriptMsg::CreateCanvasPaintThread(size, sender)).unwrap();
@@ -371,7 +372,7 @@ impl CanvasRenderingContext2D {
                 None => return Err(Error::InvalidState),
             };
 
-            let (sender, receiver) = ipc::channel().unwrap();
+            let (sender, receiver) = ipc::channel(self.global().time_profiler_chan().clone()).unwrap();
             let msg = CanvasMsg::Canvas2d(Canvas2dMsg::DrawImageInOther(
                 self.ipc_renderer.clone(),
                 image_size,
@@ -782,7 +783,7 @@ impl CanvasRenderingContext2DMethods for CanvasRenderingContext2D {
             CanvasFillRule::Nonzero => FillRule::Nonzero,
             CanvasFillRule::Evenodd => FillRule::Evenodd,
         };
-        let (sender, receiver) = ipc::channel::<bool>().unwrap();
+        let (sender, receiver) = ipc::channel::<bool>(self.global().time_profiler_chan().clone()).unwrap();
         self.ipc_renderer
             .send(CanvasMsg::Canvas2d(Canvas2dMsg::IsPointInPath(x, y, fill_rule, sender)))
             .unwrap();
@@ -1126,7 +1127,7 @@ impl CanvasRenderingContext2DMethods for CanvasRenderingContext2D {
         let sh = cmp::max(1, sh.to_u32().unwrap());
         let sw = cmp::max(1, sw.to_u32().unwrap());
 
-        let (sender, receiver) = ipc::channel::<Vec<u8>>().unwrap();
+        let (sender, receiver) = ipc::channel::<Vec<u8>>(self.global().time_profiler_chan().clone()).unwrap();
         let dest_rect = Rect::new(Point2D::new(sx.to_i32().unwrap(), sy.to_i32().unwrap()),
                                   Size2D::new(sw as i32, sh as i32));
         let canvas_size = self.canvas.as_ref().map(|c| c.get_size()).unwrap_or(Size2D::zero());