Add support for touch based zoom gesture on Windows. This change also handles the WM_POINTERDOWN

content/browser/renderer_host/render_widget_host_view_win.h

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_VIEW_WIN_H_
 #define CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_VIEW_WIN_H_
 #pragma once
 
 #include <atlbase.h>
 #include <atlapp.h>
@@ skipping 32 matching lines @@
 
 namespace ui {
 class ViewProp;
 }
 
 typedef CWinTraits<WS_CHILD | WS_CLIPCHILDREN | WS_CLIPSIBLINGS, 0>
     RenderWidgetHostHWNDTraits;
 
 CONTENT_EXPORT extern const wchar_t kRenderWidgetHostHWNDClass[];
 
+// TODO(ananta)
+// This should be removed once we have the new windows SDK which defines these
+// messages.
+#if !defined(WM_POINTERUPDATE)
+#define WM_POINTERUPDATE 0x0245
+#endif  // WM_POINTERUPDATE
+
+#if !defined(WM_POINTERDOWN)
+#define WM_POINTERDOWN  0x0246
+#endif  // WM_POINTERDOWN
+
+#if !defined(WM_POINTERUP)
+#define WM_POINTERUP    0x0247
+#endif  // WM_POINTERUP
+
 ///////////////////////////////////////////////////////////////////////////////
 // RenderWidgetHostViewWin
 //
 //  An object representing the "View" of a rendered web page. This object is
 //  responsible for displaying the content of the web page, receiving windows
 //  messages, and containing plugins HWNDs. It is the implementation of the
 //  RenderWidgetHostView that the cross-platform RenderWidgetHost object uses
 //  to display the data.
 //
 //  Comment excerpted from render_widget_host.h:
@@ skipping 59 matching lines @@
     MESSAGE_HANDLER(WM_MOUSEWHEEL, OnWheelEvent)
     MESSAGE_HANDLER(WM_MOUSEHWHEEL, OnWheelEvent)
     MESSAGE_HANDLER(WM_HSCROLL, OnWheelEvent)
     MESSAGE_HANDLER(WM_VSCROLL, OnWheelEvent)
     MESSAGE_HANDLER(WM_CHAR, OnKeyEvent)
     MESSAGE_HANDLER(WM_SYSCHAR, OnKeyEvent)
     MESSAGE_HANDLER(WM_IME_CHAR, OnKeyEvent)
     MESSAGE_HANDLER(WM_MOUSEACTIVATE, OnMouseActivate)
     MESSAGE_HANDLER(WM_GETOBJECT, OnGetObject)
     MESSAGE_HANDLER(WM_PARENTNOTIFY, OnParentNotify)
+    MESSAGE_HANDLER(WM_POINTERDOWN, OnPointerMessage)
+    MESSAGE_HANDLER(WM_POINTERUP, OnPointerMessage)
     MESSAGE_HANDLER(WM_GESTURE, OnGestureEvent)
   END_MSG_MAP()
 
   // Implementation of RenderWidgetHostView:
   virtual void InitAsPopup(RenderWidgetHostView* parent_host_view,
                            const gfx::Rect& pos) OVERRIDE;
   virtual void InitAsFullscreen(
       RenderWidgetHostView* reference_host_view) OVERRIDE;
   virtual RenderWidgetHost* GetRenderWidgetHost() const OVERRIDE;
   virtual void DidBecomeSelected() OVERRIDE;
@@ skipping 91 matching lines @@
   // Handle MSAA requests for accessibility information.
   LRESULT OnGetObject(UINT message, WPARAM wparam, LPARAM lparam,
                       BOOL& handled);
   // Handle vertical scrolling.
   LRESULT OnVScroll(int code, short position, HWND scrollbar_control);
   // Handle horizontal scrolling.
   LRESULT OnHScroll(int code, short position, HWND scrollbar_control);
 
   LRESULT OnParentNotify(UINT message, WPARAM wparam, LPARAM lparam,
                          BOOL& handled);
+
+  // Handle the new pointer messages
+  LRESULT OnPointerMessage(UINT message, WPARAM wparam, LPARAM lparam,
+                           BOOL& handled);
   // Handle high-level touch events.
   LRESULT OnGestureEvent(UINT message, WPARAM wparam, LPARAM lparam,
                          BOOL& handled);
 
   void OnFinalMessage(HWND window);
 
  private:
   // Updates the display cursor to the current cursor if the cursor is over this
   // render view.
   void UpdateCursorIfOverSelf();
@@ skipping 151 matching lines @@
   // lock was entered.
   // Relative to the upper-left corner of the view.
   gfx::Point last_mouse_position_;
   // Relative to the upper-left corner of the screen.
   gfx::Point last_global_mouse_position_;
 
   // In the case of the mouse being moved away from the view and then moved
   // back, we regard the mouse movement as (0, 0).
   bool ignore_mouse_movement_;
 
+  // Set to true if the next lbutton down message is to be ignored. Set by the
+  // WM_POINTERXX handler. We do this to ensure that we don't send out
+  // duplicate lbutton down messages to the renderer.
+  bool ignore_next_lbutton_message_at_same_location;
+  // The location of the last WM_POINTERDOWN message. We ignore the subsequent
+  // lbutton down only if the locations match.
+  LPARAM last_pointer_down_location_;
+
   DISALLOW_COPY_AND_ASSIGN(RenderWidgetHostViewWin);
 };
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_VIEW_WIN_H_