WebViewPlugin: Make WebView resize take place synchronously.

components/plugins/renderer/webview_plugin.cc

Index: components/plugins/renderer/webview_plugin.cc
diff --git a/components/plugins/renderer/webview_plugin.cc b/components/plugins/renderer/webview_plugin.cc
index ed0adbc0fe6950024154d026e3230004845dd7c3..9518dcb9be7f3da751934b479915092c146a3e1a 100644
--- a/components/plugins/renderer/webview_plugin.cc
+++ b/components/plugins/renderer/webview_plugin.cc
@@ -209,6 +209,13 @@ void WebViewPlugin::updateGeometry(const WebRect& window_rect,
                                    bool is_visible) {
   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());
+  }
+
   // Plugin updates are forbidden during Blink layout. Therefore,
   // UpdatePluginForNewGeometry must be posted to a task to run asynchronously.
   base::ThreadTaskRunnerHandle::Get()->PostTask(
@@ -348,19 +355,12 @@ void WebViewPlugin::UpdatePluginForNewGeometry(
     const blink::WebRect& window_rect,
     const blink::WebRect& unobscured_rect) {
   DCHECK(container_);
+  if (!delegate_)
+    return;
 
-  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();
-  }
+  delegate_->OnUnobscuredRectUpdate(gfx::Rect(unobscured_rect));

[dcheng, 2016/08/04 01:48:51]

Nit: perhaps comment that this is what can actually instantiate the plugin.

[tommycli, 2016/08/04 02:10:12]

Done.

+  // 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();
 }