OOPIF: Check whether localFrameRootTemporary is valid when processing resizing messages

Source/web/WebViewImpl.cpp

Index: Source/web/WebViewImpl.cpp
diff --git a/Source/web/WebViewImpl.cpp b/Source/web/WebViewImpl.cpp
index f5c464c3868c939b6152106cc43bfa9f8d9bca5b..761dc41775b2ea9473c89ef5b9428050bc5385f2 100644
--- a/Source/web/WebViewImpl.cpp
+++ b/Source/web/WebViewImpl.cpp
@@ -1712,7 +1712,11 @@ void WebViewImpl::setTopControlsLayoutHeight(float height)
 
 void WebViewImpl::didUpdateTopControls()
 {
-    FrameView* view = localFrameRootTemporary()->frameView();
+    WebLocalFrameImpl* localFrameRoot = localFrameRootTemporary();
+    if (!localFrameRoot)
+        return;
+
+    FrameView* view = localFrameRoot->frameView();
     if (!view)
         return;
 
@@ -1729,7 +1733,13 @@ void WebViewImpl::resize(const WebSize& newSize)
     if (m_shouldAutoResize || m_size == newSize)
         return;
 
-    FrameView* view = localFrameRootTemporary()->frameView();
+    // FIXME: if a remote frame is swapped back in, it may have the wrong
+    // sizing.

[kenrb, 2014/10/10 19:20:21]

I don't think this is a valid concern. Size messages should be destined to the
process where a frame is actually being rendered. A remote frame's embedder
knows how big the frame is supposed to be, and it is sending that size to the
process where the frame is local.

Ultimately WebViewImpl::resize() should only be called on the top-level frame,
because semantically this is declaring the size of the content viewport in the
browser window. Part of getting rid of localFrameRootTemporary() is making
WebViewImpl not have to route messages to remote frames.

+    WebLocalFrameImpl* localFrameRoot = localFrameRootTemporary();
+    if (!localFrameRoot)
+        return;
+
+    FrameView* view = localFrameRoot->frameView();
     if (!view)
         return;