Clean up the RWHVMac to ui::Compositor interface (phase 1 of 2)

chrome/browser/thumbnails/thumbnail_tab_helper.cc

 // Copyright (c) 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 "chrome/browser/thumbnails/thumbnail_tab_helper.h"
 
 #include "build/build_config.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/thumbnails/thumbnail_service.h"
@@ skipping 92 matching lines @@
 }
 
 void ThumbnailTabHelper::NavigationStopped() {
   // This function gets called when the page loading is interrupted by the
   // stop button.
   load_interrupted_ = true;
 }
 
 void ThumbnailTabHelper::UpdateThumbnailIfNecessary() {
   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
-  // Ignore thumbnail update requests if one is already in progress. This can
-  // happen at the end of thumbnail generation when
-  // CleanUpFromThumbnailGeneration() calls DecrementCapturerCount(), triggering
-  // a call to content::WebContentsImpl::WasHidden() which eventually calls
-  // ThumbnailTabHelper::UpdateThumbnailIfNecessary().
+  // Ignore thumbnail update requests if one is already in progress.
   if (thumbnailing_context_) {
     return;
   }
 
   // Destroying a WebContents may trigger it to be hidden, prompting a snapshot
   // which would be unwise to attempt <http://crbug.com/130097>. If the
   // WebContents is in the middle of destruction, do not risk it.
   if (!web_contents() || web_contents()->IsBeingDestroyed())
     return;
   // Skip if a pending entry exists. WidgetHidden can be called while navigating
   // pages and this is not a time when thumbnails should be generated.
   if (web_contents()->GetController().GetPendingEntry())
     return;
   const GURL& url = web_contents()->GetURL();
   Profile* profile =
       Profile::FromBrowserContext(web_contents()->GetBrowserContext());
 
   scoped_refptr<thumbnails::ThumbnailService> thumbnail_service =
       ThumbnailServiceFactory::GetForProfile(profile);
 
   // Skip if we don't need to update the thumbnail.
   if (thumbnail_service.get() == NULL ||
       !thumbnail_service->ShouldAcquirePageThumbnail(url)) {
     return;
   }
 
-  // Prevent the web contents from disappearing before the async thumbnail
-  // generation code executes. See https://crbug.com/530707 .
-  web_contents()->IncrementCapturerCount(gfx::Size());
-
   AsyncProcessThumbnail(thumbnail_service);
 }
 
 void ThumbnailTabHelper::AsyncProcessThumbnail(
     scoped_refptr<thumbnails::ThumbnailService> thumbnail_service) {
   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
   RenderWidgetHost* render_widget_host =
       web_contents()->GetRenderViewHost()->GetWidget();
   content::RenderWidgetHostView* view = render_widget_host->GetView();
   if (!view || !view->IsSurfaceAvailableForCopy()) {
@@ skipping 51 matching lines @@
     // that cleanup happens on that thread.
     content::BrowserThread::PostTask(
         content::BrowserThread::UI,
         FROM_HERE,
         base::Bind(&ThumbnailTabHelper::CleanUpFromThumbnailGeneration,
                    weak_factory_.GetWeakPtr()));
   }
 }
 
 void ThumbnailTabHelper::CleanUpFromThumbnailGeneration() {
-  if (web_contents()) {
-    // Balance the call to IncrementCapturerCount() made in
-    // UpdateThumbnailIfNecessary().
-    web_contents()->DecrementCapturerCount();
-  }
-
   // Make a note that thumbnail generation is complete.
   thumbnailing_context_ = nullptr;
 }
 
 void ThumbnailTabHelper::UpdateThumbnail(
     const thumbnails::ThumbnailingContext& context,
     const SkBitmap& thumbnail) {
   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
   // Feed the constructed thumbnail to the thumbnail service.
   gfx::Image image = gfx::Image::CreateFrom1xBitmap(thumbnail);
@@ skipping 14 matching lines @@
       content::Source<RenderWidgetHost>(renderer->GetWidget()));
   if (!registered) {
     registrar_.Add(this, content::NOTIFICATION_RENDER_WIDGET_VISIBILITY_CHANGED,
                    content::Source<RenderWidgetHost>(renderer->GetWidget()));
   }
 }
 
 void ThumbnailTabHelper::WidgetHidden(RenderWidgetHost* widget) {
   UpdateThumbnailIfNecessary();
 }