Adds DevTools commands for forced viewport override.

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 f274fb4f6962e807ca2ccf2a3604237a8e378785..775fab410eaa626a5453a41c506b01ecb8994751 100644
--- a/third_party/WebKit/Source/web/ChromeClientImpl.cpp
+++ b/third_party/WebKit/Source/web/ChromeClientImpl.cpp
@@ -104,6 +104,7 @@
 #include "web/ColorChooserPopupUIController.h"
 #include "web/ColorChooserUIController.h"
 #include "web/DateTimeChooserImpl.h"
+#include "web/DevToolsEmulator.h"
 #include "web/ExternalDateTimeChooser.h"
 #include "web/ExternalPopupMenu.h"
 #include "web/IndexedDBClientImpl.h"
@@ -118,6 +119,7 @@
 #include "web/WebPluginContainerImpl.h"
 #include "web/WebSettingsImpl.h"
 #include "web/WebViewImpl.h"
+#include "wtf/Optional.h"
 #include "wtf/PtrUtil.h"
 #include "wtf/text/CString.h"
 #include "wtf/text/CharacterNames.h"
@@ -608,6 +610,11 @@ WebScreenInfo ChromeClientImpl::screenInfo() const
     return m_webView->client() ? m_webView->client()->screenInfo() : WebScreenInfo();
 }
 
+WTF::Optional<IntRect> ChromeClientImpl::visibleContentRectForPainting() const
+{
+    return m_webView->devToolsEmulator()->visibleContentRectForPainting();
+}
+
 void ChromeClientImpl::contentsSizeChanged(LocalFrame* frame, const IntSize& size) const
 {
     m_webView->didChangeContentsSize();
@@ -621,6 +628,11 @@ void ChromeClientImpl::pageScaleFactorChanged() const
     m_webView->pageScaleFactorChanged();
 }
 
+void ChromeClientImpl::mainFrameScrollOffsetChanged() const
+{
+    m_webView->mainFrameScrollOffsetChanged();
+}
+
 float ChromeClientImpl::clampPageScaleFactorToLimits(float scale) const
 {
     return m_webView->clampPageScaleFactorToLimits(scale);