Send early ShowPress on TapDown when page isn't scrollable/pinchable.

Source/web/WebViewImpl.h

Index: Source/web/WebViewImpl.h
diff --git a/Source/web/WebViewImpl.h b/Source/web/WebViewImpl.h
index e686c2288e7fb009b22e02fd9217d4dc0cb17601..4d082f87e937e1693d08a7bedb944f256422925d 100644
--- a/Source/web/WebViewImpl.h
+++ b/Source/web/WebViewImpl.h
@@ -527,6 +527,8 @@ public:
 
     WebLayerTreeView* layerTreeView() const { return m_layerTreeView; }
 
+    bool isPinchZoomable() const;
+
 private:
     float legibleScale() const;
     void refreshPageScaleFactorAfterLayout();
@@ -603,6 +605,8 @@ private:
     virtual bool handleKeyEvent(const WebKeyboardEvent&) OVERRIDE;
     virtual bool handleCharEvent(const WebKeyboardEvent&) OVERRIDE;
 
+    bool earlyGestureShowPress(const WebCore::PlatformGestureEvent&);
+
     WebCore::InputMethodContext* inputMethodContext();
     WebPlugin* focusedPluginIfInputMethodSupported(WebCore::LocalFrame*);
 
@@ -771,6 +775,7 @@ private:
     WebColor m_baseBackgroundColor;
     WebColor m_backgroundColorOverride;
     float m_zoomFactorOverride;
+    bool m_sentEarlyShowPress;
 };
 
 // We have no ways to check if the specified WebView is an instance of