WebViewPlugin: Post geometry-update actions to a task to run async.

components/plugins/renderer/webview_plugin.cc

 // Copyright 2013 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 "components/plugins/renderer/webview_plugin.h"
 
 #include <stddef.h>
 
 #include "base/auto_reset.h"
+#include "base/bind.h"
 #include "base/location.h"
 #include "base/metrics/histogram_macros.h"
 #include "base/numerics/safe_conversions.h"
 #include "base/single_thread_task_runner.h"
 #include "base/threading/thread_task_runner_handle.h"
 #include "content/public/common/web_preferences.h"
 #include "content/public/renderer/render_view.h"
 #include "gin/converter.h"
 #include "skia/ext/platform_canvas.h"
 #include "third_party/WebKit/public/platform/WebSize.h"
@@ skipping 33 matching lines @@
 WebViewPlugin::WebViewPlugin(content::RenderView* render_view,
                              WebViewPlugin::Delegate* delegate,
                              const WebPreferences& preferences)
     : content::RenderViewObserver(render_view),
       delegate_(delegate),
       container_(nullptr),
       web_view_(WebView::create(this, blink::WebPageVisibilityStateVisible)),
       finished_loading_(false),
       focused_(false),
       is_painting_(false),
-      is_resizing_(false) {
+      is_resizing_(false),
+      weak_factory_(this) {
   // ApplyWebPreferences before making a WebLocalFrame so that the frame sees a
   // consistent view of our preferences.
   content::RenderView::ApplyWebPreferences(preferences, web_view_);
   WebLocalFrame* web_local_frame =
       WebLocalFrame::create(blink::WebTreeScopeType::Document, this);
   web_frame_ = web_local_frame;
   web_view_->setMainFrame(web_frame_);
   // TODO(dcheng): The main frame widget currently has a special case.
   // Eliminate this once WebView is no longer a WebWidget.
   web_frame_widget_ = WebFrameWidget::create(this, web_view_, web_local_frame);
 }
 
 // static
 WebViewPlugin* WebViewPlugin::Create(content::RenderView* render_view,
                                      WebViewPlugin::Delegate* delegate,
                                      const WebPreferences& preferences,
                                      const std::string& html_data,
                                      const GURL& url) {
   DCHECK(url.is_valid()) << "Blink requires the WebView to have a valid URL.";
   WebViewPlugin* plugin = new WebViewPlugin(render_view, delegate, preferences);
   plugin->web_view()->mainFrame()->loadHTMLString(html_data, url);
   return plugin;
 }
 
 WebViewPlugin::~WebViewPlugin() {
+  DCHECK(!weak_factory_.HasWeakPtrs());
   web_frame_widget_->close();
   web_view_->close();
   web_frame_->close();
 }
 
 void WebViewPlugin::ReplayReceivedData(WebPlugin* plugin) {
   if (!response_.isNull()) {
     plugin->didReceiveResponse(response_);
     size_t total_bytes = 0;
     for (std::list<std::string>::iterator it = data_.begin(); it != data_.end();
@@ skipping 46 matching lines @@
 
   // Propagate device scale and zoom level to inner webview.
   web_view_->setDeviceScaleFactor(container_->deviceScaleFactor());
   web_view_->setZoomLevel(
       blink::WebView::zoomFactorToZoomLevel(container_->pageZoomFactor()));
 
   return true;
 }
 
 void WebViewPlugin::destroy() {
+  weak_factory_.InvalidateWeakPtrs();
+
   if (delegate_) {
     delegate_->PluginDestroyed();
     delegate_ = nullptr;
   }
   container_ = nullptr;
   content::RenderViewObserver::Observe(nullptr);
   base::ThreadTaskRunnerHandle::Get()->DeleteSoon(FROM_HERE, this);
 }
 
 v8::Local<v8::Object> WebViewPlugin::v8ScriptableObject(v8::Isolate* isolate) {
@@ skipping 30 matching lines @@
 
   canvas->restore();
 }
 
 // Coordinates are relative to the containing window.
 void WebViewPlugin::updateGeometry(const WebRect& window_rect,
                                    const WebRect& clip_rect,
                                    const WebRect& unobscured_rect,
                                    const WebVector<WebRect>& cut_outs_rects,
                                    bool is_visible) {
-  base::AutoReset<bool> is_resizing(
-        &is_resizing_, true);
+  DCHECK(container_);
 
-  if (static_cast<gfx::Rect>(window_rect) != rect_) {
-    rect_ = window_rect;
-    WebSize newSize(window_rect.width, window_rect.height);
-    web_view_->resize(newSize);
-  }
-
-  if (delegate_) {
-    delegate_->OnUnobscuredRectUpdate(gfx::Rect(unobscured_rect));
-    // The delegate may have dirtied style and layout of the WebView.
-    // See for example the resizePoster function in plugin_poster.html.
-    // Run the lifecycle now so that it is clean.
-    web_view_->updateAllLifecyclePhases();
-  }
+  // Plugin updates are forbidden during Blink layout. Therefore,
+  // UpdatePluginForNewGeometry must be posted to a task to run asynchronously.
+  base::ThreadTaskRunnerHandle::Get()->PostTask(
+      FROM_HERE,
+      base::Bind(&WebViewPlugin::UpdatePluginForNewGeometry,
+                 weak_factory_.GetWeakPtr(), window_rect, unobscured_rect));
 }
 
 void WebViewPlugin::updateFocus(bool focused, blink::WebFocusType focus_type) {
   focused_ = focused;
 }
 
 blink::WebInputEventResult WebViewPlugin::handleInputEvent(
     const WebInputEvent& event,
     WebCursorInfo& cursor) {
   // For tap events, don't handle them. They will be converted to
@@ skipping 108 matching lines @@
 }
 
 void WebViewPlugin::OnDestruct() {}
 
 void WebViewPlugin::OnZoomLevelChanged() {
   if (container_) {
     web_view_->setZoomLevel(
       blink::WebView::zoomFactorToZoomLevel(container_->pageZoomFactor()));
   }
 }
+
+void WebViewPlugin::UpdatePluginForNewGeometry(
+    const blink::WebRect& window_rect,
+    const blink::WebRect& unobscured_rect) {
+  DCHECK(container_);
+
+  base::AutoReset<bool> is_resizing(&is_resizing_, true);
+
+  if (static_cast<gfx::Rect>(window_rect) != rect_) {
+    rect_ = window_rect;
+    web_view_->resize(rect_.size());
+  }
+
+  if (delegate_) {
+    delegate_->OnUnobscuredRectUpdate(gfx::Rect(unobscured_rect));
+    // The delegate may have dirtied style and layout of the WebView.
+    // See for example the resizePoster function in plugin_poster.html.
+    // Run the lifecycle now so that it is clean.
+    web_view_->updateAllLifecyclePhases();
+  }
+}