Propagate pageScaleFactor to GuestViews

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 6b1407b78e0ace939218a24a5478b0c23d48f1c3..d5585bbad278bdbefa61112f7021e822305aaf2d 100644
--- a/content/browser/web_contents/web_contents_impl.cc
+++ b/content/browser/web_contents/web_contents_impl.cc
@@ -413,6 +413,7 @@ WebContentsImpl::WebContentsImpl(BrowserContext* browser_context)
           BrowserAccessibilityStateImpl::GetInstance()->accessibility_mode()),
       audio_stream_monitor_(this),
       virtual_keyboard_requested_(false),
+      page_scale_factor_is_one_(true),
       loading_weak_factory_(this) {
   frame_tree_.SetFrameRemoveListener(
       base::Bind(&WebContentsImpl::OnFrameRemoved,
@@ -637,6 +638,8 @@ bool WebContentsImpl::OnMessageReceived(RenderViewHost* render_view_host,
                         OnDidRunInsecureContent)
     IPC_MESSAGE_HANDLER(ViewHostMsg_GoToEntryAtOffset, OnGoToEntryAtOffset)
     IPC_MESSAGE_HANDLER(ViewHostMsg_UpdateZoomLimits, OnUpdateZoomLimits)
+    IPC_MESSAGE_HANDLER(ViewHostMsg_PageScaleFactorChanged,
+                        OnPageScaleFactorChanged)
     IPC_MESSAGE_HANDLER(ViewHostMsg_EnumerateDirectory, OnEnumerateDirectory)
     IPC_MESSAGE_HANDLER(FrameHostMsg_RegisterProtocolHandler,
                         OnRegisterProtocolHandler)
@@ -2628,8 +2631,8 @@ int WebContentsImpl::GetMaximumZoomPercent() const {
   return maximum_zoom_percent_;
 }
 
-void WebContentsImpl::ResetPageScale() {
-  Send(new ViewMsg_ResetPageScale(GetRoutingID()));
+void WebContentsImpl::SetPageScale(float page_scale_factor) {
+  Send(new ViewMsg_SetPageScale(GetRoutingID(), page_scale_factor));
 }
 
 gfx::Size WebContentsImpl::GetPreferredSize() const {
@@ -2968,6 +2971,14 @@ void WebContentsImpl::DidNavigateMainFramePostCommit(
 
     // Reset theme color on navigation to new page.
     theme_color_ = SK_ColorTRANSPARENT;
+
+    // We need the renderer to send us its page scale factor
+    // so that we have a notification for the inital page scale factor,
+    // and so that we are notified upon navigation to a page with a default
+    // page scale factor (notifications about resetting the page scale factor
+    // upon navigation are filtered in the RenderView while it's swapped out
+    // so we ask for it again here).
+    Send(new ViewMsg_GetPageScale(GetRoutingID()));

[Charlie Reis, 2015/10/30 18:42:58]

This doesn't make sense to me.  The renderer process has just told us that it
navigated, and now the browser process is turning around and telling it to do
something extra.  (This method should be about notifications going up to other
things in the browser process to let them know the navigation occurred.)

Is there a reason we can't just call render_view_->pageScaleFactorChanged() from
somewhere in RenderFrameImpl when the commit happens?  At first glance, I'm
looking at something like this:

https://code.google.com/p/chromium/codesearch#chromium/src/content/renderer/r...

[Kevin McNee - google account, 2015/10/30 21:41:31]

Done.

Yeah, that works.

   }
 
   if (!details.is_in_page) {
@@ -3127,6 +3138,26 @@ void WebContentsImpl::OnUpdateZoomLimits(int minimum_percent,
   maximum_zoom_percent_ = maximum_percent;
 }
 
+void WebContentsImpl::OnPageScaleFactorChanged(float page_scale_factor) {
+  bool is_one = page_scale_factor == 1.f;
+  if (is_one != page_scale_factor_is_one_) {
+    page_scale_factor_is_one_ = is_one;
+
+    HostZoomMapImpl* host_zoom_map =
+        static_cast<HostZoomMapImpl*>(HostZoomMap::GetForWebContents(this));
+
+    if (host_zoom_map && GetRenderProcessHost()) {
+      host_zoom_map->SetPageScaleFactorIsOneForView(
+          GetRenderProcessHost()->GetID(), GetRoutingID(),
+          page_scale_factor_is_one_);
+    }
+  }
+
+  FOR_EACH_OBSERVER(WebContentsObserver,
+                    observers_,
+                    OnPageScaleFactorChanged(page_scale_factor));
+}
+
 void WebContentsImpl::OnEnumerateDirectory(int request_id,
                                            const base::FilePath& path) {
   if (!delegate_)