Fix visual viewport for OOPIF.

third_party/WebKit/Source/web/WebFrameWidgetImpl.cpp

 /*
  * Copyright (C) 2014 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 17 matching lines @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #include "web/WebFrameWidgetImpl.h"
 
 #include "core/editing/EditingUtilities.h"
 #include "core/editing/Editor.h"
 #include "core/editing/FrameSelection.h"
 #include "core/editing/InputMethodController.h"
 #include "core/editing/PlainTextRange.h"
+#include "core/frame/FrameHost.h"
 #include "core/frame/FrameView.h"
 #include "core/frame/RemoteFrame.h"
 #include "core/frame/Settings.h"
 #include "core/input/EventHandler.h"
 #include "core/layout/LayoutView.h"
 #include "core/layout/compositing/PaintLayerCompositor.h"
 #include "core/page/ContextMenuController.h"
 #include "core/page/FocusController.h"
 #include "core/page/Page.h"
 #include "platform/KeyboardCodes.h"
@@ skipping 144 matching lines @@
             updateLayerTreeViewport();
         } else {
             WebRect damagedRect(0, 0, m_size.width, m_size.height);
             m_client->didInvalidateRect(damagedRect);
         }
     }
 }
 
 void WebFrameWidgetImpl::resizeVisualViewport(const WebSize& newSize)
 {
-    // FIXME: Implement visual viewport for out-of-process iframes.
+    page()->frameHost().visualViewport().setSize(newSize);
+    page()->frameHost().visualViewport().clampToBoundaries();

[alexmos, 2016/03/26 00:00:48]

Note that I didn't have to add any plumbing for sending resize messages for
OOPIFs, as this kind of happens for free today.  Here's the flow of events when
you resize the window:
- ViewMsg_Resize is sent to main frame's renderer
- eventually, this hits FrameView::frameRectsChanged(), which goes and calls
frameRectsChanged on its children and hits RemoteFrameView::frameRectsChanged()
for an OOPIF.
- that sends FrameHostMsg_FrameRectChanged back to browser via the proxy.
- browser calls CrossProcessFrameConnector::SetRect()
- that gets to RenderWidgetHostViewChildFrame::SetSize(), which calls
RenderWidgetHostImpl::WasResized().
- before this CL, no resize message would be sent because ResizeParams stayed
the same.  But now that RenderWidgetHostViewChildFrame::GetVisibleViewportSize()
returns a different viewport size (due to window resize), this proceeds to send
ViewMsg_Resize to the subframe widget.
- RenderWidget::Resize() calls WebWidget::resizeVisualViewport(), which ends up
here.

We could probably optimize this in the future to avoid the extra roundtrip.

[kenrb, 2016/03/31 17:41:58]

Eventually we might want to change some of the resizing behavior to Page
messages. It doesn't seem like the visual viewport should be set once for each
local root. This isn't a high priority, but I might suggest filing a bug for
that so we can get around to it at some point.

[alexmos, 2016/03/31 23:03:47]

Good point.  I suppose this means that in cases like A-B-A we might have some
redundant updates.  I filed https://crbug.com/599688 and referenced here.

 }
 
 void WebFrameWidgetImpl::updateMainFrameLayoutSize()
 {
     if (!m_localRoot)
         return;
 
     RefPtrWillBeRawPtr<FrameView> view = m_localRoot->frameView();
     if (!view)
         return;
@@ skipping 880 matching lines @@
 
 HitTestResult WebFrameWidgetImpl::hitTestResultForRootFramePos(const IntPoint& posInRootFrame)
 {
     IntPoint docPoint(m_localRoot->frame()->view()->rootFrameToContents(posInRootFrame));
     HitTestResult result = m_localRoot->frame()->eventHandler().hitTestResultAtPoint(docPoint, HitTestRequest::ReadOnly | HitTestRequest::Active);
     result.setToShadowHostIfInUserAgentShadowRoot();
     return result;
 }
 
 } // namespace blink