Compute the popup location/size correctly when use-zoom-for-dsf is enabled.

third_party/WebKit/Source/web/ChromeClientImpl.cpp

 /*
  * Copyright (C) 2009 Google Inc. All rights reserved.
  * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
  *
  * 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.
@@ skipping 491 matching lines @@
 {
     ASSERT(WebLocalFrameImpl::fromFrame(localRoot));
     // If the frame is still being created, it might not yet have a WebWidget.
     // FIXME: Is this the right thing to do? Is there a way to avoid having
     // a local frame root that doesn't have a WebWidget? During initialization
     // there is no content to draw so this call serves no purpose.
     if (WebLocalFrameImpl::fromFrame(localRoot)->frameWidget())
         toWebFrameWidgetImpl(WebLocalFrameImpl::fromFrame(localRoot)->frameWidget())->scheduleAnimation();
 }
 
 IntRect ChromeClientImpl::viewportToScreen(const IntRect& rectInViewport) const

[tkent, 2015/11/18 07:06:39]

We can't change the behavior of this function.  The result is exposed to web
authors.
e.g.
https://code.google.com/p/chromium/codesearch#chromium/src/third_party/WebKit...

We need to introduce another function like viewportToPhysicalScreen().

[oshima, 2015/11/18 13:03:24]

Yes, this is to keep the same behavior in zoom-for-dsf mode. This still maps to
DIP, not physical pixels.

 {
-    IntRect screenRect(rectInViewport);
+    WebRect screenRect(rectInViewport);
 
-    if (m_webView->client()) {
-        WebRect windowRect = m_webView->client()->windowRect();
-        screenRect.move(windowRect.x, windowRect.y);
-    }
+    if (m_webView->client())
+        m_webView->client()->convertViewportToScreen(&screenRect);
 
     return screenRect;
 }
 
 WebScreenInfo ChromeClientImpl::screenInfo() const
 {
     return m_webView->client() ? m_webView->client()->screenInfo() : WebScreenInfo();
 }
 
 void ChromeClientImpl::contentsSizeChanged(LocalFrame* frame, const IntSize& size) const
@@ skipping 479 matching lines @@
     if (m_webView->pageImportanceSignals())
         m_webView->pageImportanceSignals()->setIssuedNonGetFetchFromScript();
 }
 
 PassOwnPtr<WebFrameScheduler> ChromeClientImpl::createFrameScheduler()
 {
     return m_webView->scheduler()->createFrameScheduler().release();
 }
 
 } // namespace blink