Switch the inheritance of WebViewClient from WebWidgetClient to protected.

third_party/WebKit/Source/web/ChromeClientImpl.cpp

Index: third_party/WebKit/Source/web/ChromeClientImpl.cpp
diff --git a/third_party/WebKit/Source/web/ChromeClientImpl.cpp b/third_party/WebKit/Source/web/ChromeClientImpl.cpp
index c3acd08f5f04e4e600fdc4107904a0f8568faeb9..03f19518d0827daf5c716d0caf13ac11b59c1281 100644
--- a/third_party/WebKit/Source/web/ChromeClientImpl.cpp
+++ b/third_party/WebKit/Source/web/ChromeClientImpl.cpp
@@ -565,20 +565,28 @@ IntRect ChromeClientImpl::viewportToScreen(const IntRect& rectInViewport, const
     DCHECK(widget->isFrameView());
     const FrameView* view = toFrameView(widget);
     LocalFrame* frame = view->frame().localFrameRoot();
-    WebWidgetClient* client = nullptr;
 
     // TODO(kenrb): Consolidate this to a single case when WebViewFrameWidget refactor is complete.
-    if (WebLocalFrameImpl::fromFrame(frame) && WebLocalFrameImpl::fromFrame(frame)->frameWidget() && WebLocalFrameImpl::fromFrame(frame)->frameWidget()->forSubframe())
-        client = toWebFrameWidgetImpl(WebLocalFrameImpl::fromFrame(frame)->frameWidget())->client();
-    else
-        client = m_webView->client();
+    if (WebLocalFrameImpl::fromFrame(frame) && WebLocalFrameImpl::fromFrame(frame)->frameWidget() && WebLocalFrameImpl::fromFrame(frame)->frameWidget()->forSubframe()) {

[dcheng, 2016/04/27 23:55:04]

I previously tried to remove this and failed, because we didn't have a test web
widget client.

Maybe we can just remove this branching completely now?

[lfg, 2016/04/28 17:04:33]

I removed the branch but had to add a virtual to WebFrameWidget to get the
client. I think this should be acceptable until we can remove the
WebViewFrameWidget.

+        WebWidgetClient* client = toWebFrameWidgetImpl(WebLocalFrameImpl::fromFrame(frame)->frameWidget())->client();
+
+        if (client) {
+            client->convertViewportToWindow(&screenRect);
+            WebRect windowRect = client->windowRect();
+            screenRect.x += windowRect.x;
+            screenRect.y += windowRect.y;
+        }
+    } else {
+        WebViewClient* client = m_webView->client();
 
-    if (client) {
-        client->convertViewportToWindow(&screenRect);
-        WebRect windowRect = client->windowRect();
-        screenRect.x += windowRect.x;
-        screenRect.y += windowRect.y;
+        if (client) {
+            client->convertViewportToWindow(&screenRect);
+            WebRect windowRect = client->windowRect();
+            screenRect.x += windowRect.x;
+            screenRect.y += windowRect.y;
+        }
     }
+
     return screenRect;
 }