Add initial support for handling touch events in desktop chrome AURA.

ui/views/win/hwnd_message_handler.cc

Index: ui/views/win/hwnd_message_handler.cc
===================================================================
--- ui/views/win/hwnd_message_handler.cc	(revision 174871)
+++ ui/views/win/hwnd_message_handler.cc	(working copy)
@@ -295,6 +295,10 @@
 // The thickness of an auto-hide taskbar in pixels.
 const int kAutoHideTaskbarThicknessPx = 2;
 
+// The touch id to be used for touch events coming in from Windows Aura
+// Desktop.
+const int kDesktopChromeAuraTouchId = 9;

[sky, 2013/01/07 15:53:45]

Do we need to make sure this doesn't conflict with anything?

[ananta, 2013/01/08 00:50:22]

We shouldn't be conflicting with anything. We have a limit of 12 touch event
sources with only one among them being active in a session. Exception being ASH
and desktop Chrome. Ash uses 10 as the touch id and desktop chrome with this
change will use 9.

+
 }  // namespace
 
 // A scoping class that prevents a window from being able to redraw in response
@@ -1974,10 +1978,27 @@
   if (GetTouchInputInfo(reinterpret_cast<HTOUCHINPUT>(l_param),
                         num_points, input.get(), sizeof(TOUCHINPUT))) {
     for (int i = 0; i < num_points; ++i) {
-      if (input[i].dwFlags & TOUCHEVENTF_DOWN)
+      ui::EventType touch_event_type = ui::ET_UNKNOWN;
+
+      if (input[i].dwFlags & TOUCHEVENTF_DOWN) {
         touch_ids_.insert(input[i].dwID);
-      if (input[i].dwFlags & TOUCHEVENTF_UP)
+        touch_event_type = ui::ET_TOUCH_PRESSED;
+      } else if (input[i].dwFlags & TOUCHEVENTF_UP) {
         touch_ids_.erase(input[i].dwID);
+        touch_event_type = ui::ET_TOUCH_RELEASED;
+      } else if (input[i].dwFlags & TOUCHEVENTF_MOVE) {
+        touch_event_type = ui::ET_TOUCH_MOVED;
+      }
+
+      if (touch_event_type != ui::ET_UNKNOWN) {
+        ui::TouchEvent event(
+            touch_event_type,
+            gfx::Point(TOUCH_COORD_TO_PIXEL(input[i].x),
+                       TOUCH_COORD_TO_PIXEL(input[i].y)),
+            kDesktopChromeAuraTouchId,
+            base::TimeDelta::FromMilliseconds(input[i].dwTime));
+        delegate_->HandleTouchEvent(event);
+      }
     }
   }
   CloseTouchInputHandle(reinterpret_cast<HTOUCHINPUT>(l_param));