aw: Add more trace events to drawing functions

android_webview/native/aw_contents.cc

 // Copyright 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "android_webview/native/aw_contents.h"
 
 #include <limits>
 
 #include "android_webview/browser/aw_browser_context.h"
 #include "android_webview/browser/aw_browser_main_parts.h"
@@ skipping 863 matching lines @@
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   gfx::Vector2d scroll(scroll_x, scroll_y);
   browser_view_renderer_.PrepareToDraw(
       scroll, gfx::Rect(visible_left, visible_top, visible_right - visible_left,
                         visible_bottom - visible_top));
   if (is_hardware_accelerated && browser_view_renderer_.attached_to_window()) {
     return browser_view_renderer_.OnDrawHardware();
   }
 
   gfx::Size view_size = browser_view_renderer_.size();
-  if (view_size.IsEmpty())
+  if (view_size.IsEmpty()) {
+    TRACE_EVENT_INSTANT0("android_webview", "EarlyOut_EmptySize",
+                         TRACE_EVENT_SCOPE_THREAD);
     return false;
+  }
 
   // TODO(hush): Right now webview size is passed in as the auxiliary bitmap
   // size, which might hurt performace (only for software draws with auxiliary
   // bitmap). For better performance, get global visible rect, transform it
   // from screen space to view space, then intersect with the webview in
   // viewspace.  Use the resulting rect as the auxiliary bitmap.
   scoped_ptr<SoftwareCanvasHolder> canvas_holder =
       SoftwareCanvasHolder::Create(canvas, scroll, view_size);
-  if (!canvas_holder || !canvas_holder->GetCanvas())
+  if (!canvas_holder || !canvas_holder->GetCanvas()) {
+    TRACE_EVENT_INSTANT0("android_webview", "EarlyOut_EmptySize",
+                         TRACE_EVENT_SCOPE_THREAD);
     return false;
+  }
   return browser_view_renderer_.OnDrawSoftware(canvas_holder->GetCanvas());
 }
 
 void AwContents::SetPendingWebContentsForPopup(
     scoped_ptr<content::WebContents> pending) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   if (pending_contents_.get()) {
     // TODO(benm): Support holding multiple pop up window requests.
     LOG(WARNING) << "Blocking popup window creation as an outstanding "
                  << "popup window is still pending.";
@@ skipping 212 matching lines @@
                  base::Owned(port1),
                  base::Owned(port2)));
 }
 
 
 void SetShouldDownloadFavicons(JNIEnv* env, jclass jclazz) {
   g_should_download_favicons = true;
 }
 
 }  // namespace android_webview