Add LayerTreeHostClient::{will,did}UpdateLayer, report layer updates to DevTools

content/renderer/render_view_impl.cc

Index: content/renderer/render_view_impl.cc
diff --git a/content/renderer/render_view_impl.cc b/content/renderer/render_view_impl.cc
index 288b40586cccc55ad6e92949f912d9bbd64d3404..ecc845d05b13ca481a64739a8b0dcc2f3e9274a7 100644
--- a/content/renderer/render_view_impl.cc
+++ b/content/renderer/render_view_impl.cc
@@ -939,8 +939,10 @@ void RenderViewImpl::Initialize(RenderViewImplParams* params) {
   // The next group of objects all implement RenderViewObserver, so are deleted
   // along with the RenderView automatically.
   devtools_agent_ = new DevToolsAgent(this);
+  if (RenderWidgetCompositor* rwc = compositor()) {
+    webview()->devToolsAgent()->setLayerTreeId(rwc->GetLayerTreeId());

[jamesr, 2013/07/22 18:01:02]

hmm, why is this grabbing the devtools agent via the webview? is it different
from the devtools_agent_ parameter allocated on the previous line?

[caseq, 2013/07/22 18:56:47]

Yes, it's different: webview() returns WebKit::WebView, so its devToolsAgent()
returns WebKit::WebDevToolsAgent, not the chromium-side DevToolsAgent. Another
way to say that would be
devtools_agent_->GetWebAgent() (but that would expand to
webview()->devToolsAgent() plus null checks).

+  }
   mouse_lock_dispatcher_ = new RenderViewMouseLockDispatcher(this);
-
   new ImageLoadingHelper(this);
 
   // Create renderer_accessibility_ if needed.
@@ -2815,6 +2817,14 @@ void RenderViewImpl::didHandleGestureEvent(
                     DidHandleGestureEvent(event));
 }
 
+void RenderViewImpl::initializeLayerTreeView() {
+  RenderWidget::initializeLayerTreeView();
+  RenderWidgetCompositor* rwc = compositor();
+  if (!rwc || !webview() || !webview()->devToolsAgent())
+    return;
+  webview()->devToolsAgent()->setLayerTreeId(rwc->GetLayerTreeId());
+}
+
 // WebKit::WebFrameClient -----------------------------------------------------
 
 WebKit::WebPlugin* RenderViewImpl::createPlugin(WebFrame* frame,