Plugin Power Saver: Implement size-based heuristic for peripheral content.

content/browser/web_contents/web_contents_impl.cc

Index: content/browser/web_contents/web_contents_impl.cc
diff --git a/content/browser/web_contents/web_contents_impl.cc b/content/browser/web_contents/web_contents_impl.cc
index 4ce4f972db0f278193541181710e527129cdb364..106e94195df3027d10828f1199e353b8587a71d7 100644
--- a/content/browser/web_contents/web_contents_impl.cc
+++ b/content/browser/web_contents/web_contents_impl.cc
@@ -493,6 +493,10 @@ bool WebContentsImpl::OnMessageReceived(RenderViewHost* render_view_host,
   IPC_BEGIN_MESSAGE_MAP(WebContentsImpl, message)
     IPC_MESSAGE_HANDLER(FrameHostMsg_PepperPluginHung, OnPepperPluginHung)
     IPC_MESSAGE_HANDLER(FrameHostMsg_PluginCrashed, OnPluginCrashed)
+    IPC_MESSAGE_HANDLER(FrameHostMsg_PluginContentOriginAllowed,
+                        OnPluginContentOriginAllowed)
+    IPC_MESSAGE_HANDLER(FrameHostMsg_PluginContentMarkedPeripheral,
+                        OnPluginContentMarkedPeripheral)
     IPC_MESSAGE_HANDLER(FrameHostMsg_DomOperationResponse,
                         OnDomOperationResponse)
     IPC_MESSAGE_HANDLER(FrameHostMsg_DidChangeThemeColor,
@@ -2899,6 +2903,48 @@ void WebContentsImpl::OnPluginCrashed(const base::FilePath& plugin_path,
                     PluginCrashed(plugin_path, plugin_pid));
 }
 
+void WebContentsImpl::OnPluginContentOriginAllowed(const GURL& content_origin) {
+  DCHECK(render_frame_message_source_);
+  DCHECK(!render_view_message_source_);
+
+  plugin_content_origin_whitelist_[render_frame_message_source_].insert(

[groby-ooo-7-16, 2014/10/28 00:39:12]

Why is this a map keyed by renderframe? AFAICT, we never look up by frame and
always traverse the whole thing?

[Lei Zhang, 2014/10/28 02:16:23]

I think it's just being used to limit the number of RenderFrames we send IPCs
to. I guess this all depends on how costly it is to broadcast to all frames. jam
or nasko can probably tell you? If we do end up broadcasting to all frames, we
probably don't need FrameHostMsg_PluginContentMarkedPeripheral.

+      content_origin);
+
+  // Broadcast whitelisting to all render frames with plugin content from this
+  // origin thas has already been marked peripheral.
+  for (auto peripheral_plugin_origins : plugin_content_marked_peripheral_) {
+    if (peripheral_plugin_origins.second.erase(content_origin) > 0) {

[groby-ooo-7-16, 2014/10/28 00:39:11]

Hm. Is that necessary? The message is broadcast anyways, can we just send it to
all renderframes? Or is that cost-prohibitive?

If it is: It feels like the set of plugin origins should be stored per frame,
not on WebContents. We only need WebContents for the document-wide whitelist,
right?

[tommycli, 2014/10/28 22:18:07]

The WebContents needs to aggregate all the per-frame whitelists to send to all
the RenderFrames.

+      Send(new FrameMsg_PluginContentOriginWhitelisted(
+          peripheral_plugin_origins.first->GetRoutingID(),
+          content_origin));
+    }
+  }
+}
+
+void WebContentsImpl::OnPluginContentMarkedPeripheral(
+    const GURL& content_origin) {
+  DCHECK(render_frame_message_source_);
+  DCHECK(!render_view_message_source_);
+
+  bool origin_already_whitelisted = false;
+  for (auto whitelisted_plugin_origins : plugin_content_origin_whitelist_) {
+    if (whitelisted_plugin_origins.second.find(content_origin) !=

[groby-ooo-7-16, 2014/10/28 00:39:11]

Since you're just checking for set membership: 

if (whitelisted_plugin_origins.count(content_origin)) {
 ...
}

does the same, but is shorter.

[tommycli, 2014/10/28 22:18:07]

Done.

+        whitelisted_plugin_origins.second.end()) {
+      origin_already_whitelisted = true;
+      break;
+    }
+  }
+
+  if (origin_already_whitelisted) {
+    Send(new FrameMsg_PluginContentOriginWhitelisted(
+        render_frame_message_source_->GetRoutingID(),
+        content_origin));
+  } else {
+    plugin_content_marked_peripheral_[render_frame_message_source_].insert(
+        content_origin);
+  }
+}
+
 void WebContentsImpl::OnDomOperationResponse(const std::string& json_string,
                                              int automation_id) {
   DomOperationNotificationDetails details(json_string, automation_id);
@@ -3336,6 +3382,8 @@ void WebContentsImpl::RenderFrameCreated(RenderFrameHost* render_frame_host) {
 
 void WebContentsImpl::RenderFrameDeleted(RenderFrameHost* render_frame_host) {
   ClearPowerSaveBlockers(render_frame_host);
+  plugin_content_origin_whitelist_.erase(render_frame_host);
+  plugin_content_marked_peripheral_.erase(render_frame_host);
   FOR_EACH_OBSERVER(WebContentsObserver,
                     observers_,
                     RenderFrameDeleted(render_frame_host));