Plugin Power Saver: Throttle 'large' plugins that appear small.

content/renderer/pepper/pepper_plugin_instance_impl.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 "content/renderer/pepper/pepper_plugin_instance_impl.h"
 
 #include "base/bind.h"
 #include "base/callback_helpers.h"
 #include "base/logging.h"
 #include "base/memory/linked_ptr.h"
@@ skipping 789 matching lines @@
 bool PepperPluginInstanceImpl::Initialize(
     const std::vector<std::string>& arg_names,
     const std::vector<std::string>& arg_values,
     bool full_frame,
     scoped_ptr<PluginInstanceThrottlerImpl> throttler) {
   DCHECK(!throttler_);
 
   if (!render_frame_)
     return false;
 
+  // Get plugin dimensions directly.
+  blink::WebElement element = container()->element();
+  blink::WebRect bounds = element.boundsInViewportSpace();
+  gfx::Size size(bounds.width, bounds.height);
+
+  // Plugins are sometimes only partially visible. This is to support content
+  // that may expand. Walk up the DOM tree here to find a parent container
+  // that is smaller, and use that as the plugin's effective visible size.
+  blink::WebNode node = element.parentNode();
+  while (!node.isNull() && node.isElementNode()) {
+    blink::WebRect bounds = node.to<WebElement>().boundsInViewportSpace();
+    size.SetToMin(gfx::Size(bounds.width, bounds.height));
+    node = node.parentNode();
+  }

[piman, 2015/03/18 01:58:57]

This seems crazy. It's also most likely wrong because you're not taking the
overflow property into account. And you shouldn't be trying to duplicate blink's
layout code.

Is the size you want the clip rect passed to ViewChanged?

[tommycli, 2015/03/19 22:10:13]

Hi piman,

The clip rect passed to ViewChanged was the first thing (of many) that I tried.
In fact, it's very-very close to what I want.

It fails when the plugin is below the fold when the page loads.

I agree that this logic fails on the overflow property.

Happy to take more suggestions.

Tommy

+
   if (is_flash_plugin_ && RenderThread::Get()) {
     RenderThread::Get()->RecordAction(
         base::UserMetricsAction("Flash.PluginInstanceCreated"));
-    blink::WebRect bounds = container()->element().boundsInViewportSpace();
-    RecordFlashSizeMetric(bounds.width, bounds.height);
+    RecordFlashSizeMetric(size.width(), size.height());
   }
 
   if (throttler) {
     throttler_ = throttler.Pass();
     throttler_->AddObserver(this);
     throttler_->Initialize(render_frame_, plugin_url_.GetOrigin(),
-                           module()->name(),
-                           container()->element().boundsInViewportSpace());
+                           module()->name(), size);
   }
 
   message_channel_ = MessageChannel::Create(this, &message_channel_object_);
 
   full_frame_ = full_frame;
 
   UpdateTouchEventRequest();
   container_->setWantsWheelEvents(IsAcceptingWheelEvents());
 
   SetGPUHistogram(ppapi::Preferences(PpapiPreferencesBuilder::Build(
@@ skipping 2483 matching lines @@
 
 void PepperPluginInstanceImpl::RecordFlashJavaScriptUse() {
   if (initialized_ && !javascript_used_ && is_flash_plugin_) {
     javascript_used_ = true;
     RenderThread::Get()->RecordAction(
         base::UserMetricsAction("Flash.JavaScriptUsed"));
   }
 }
 
 }  // namespace content