Add maxTouchPoints for pointer events

Source/modules/pointerevents/NavigatorPointerEvents.cpp

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
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  * modification, are permitted provided that the following conditions are
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  *     * Redistributions in binary form must reproduce the above
@@ skipping 11 matching lines @@
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  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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 #include "config.h"
-#include "modules/donottrack/NavigatorDoNotTrack.h"
+#include "modules/pointerevents/NavigatorPointerEvents.h"
 
 #include "core/loader/FrameLoader.h"
 #include "core/loader/FrameLoaderClient.h"
 #include "core/page/Frame.h"
 #include "core/page/Navigator.h"
 #include "wtf/PassOwnPtr.h"
 
 namespace WebCore {
 
-NavigatorDoNotTrack::NavigatorDoNotTrack(Frame* frame)
+NavigatorPointerEvents::NavigatorPointerEvents(Frame* frame)
     : DOMWindowProperty(frame)
 {
 }
 
-NavigatorDoNotTrack::~NavigatorDoNotTrack()
+NavigatorPointerEvents::~NavigatorPointerEvents()
 {
 }
 
-const char* NavigatorDoNotTrack::supplementName()
+const char* NavigatorPointerEvents::supplementName()
 {
-    return "NavigatorDoNotTrack";
+    return "NavigatorPointerEvents";
 }
 
-NavigatorDoNotTrack* NavigatorDoNotTrack::from(Navigator* navigator)
+NavigatorPointerEvents* NavigatorPointerEvents::from(Navigator* navigator)
 {
-    NavigatorDoNotTrack* supplement = static_cast<NavigatorDoNotTrack*>(Supplement<Navigator>::from(navigator, supplementName()));
+    NavigatorPointerEvents* supplement = static_cast<NavigatorPointerEvents*>(Supplement<Navigator>::from(navigator, supplementName()));
     if (!supplement) {
-        supplement = new NavigatorDoNotTrack(navigator->frame());
+        supplement = new NavigatorPointerEvents(navigator->frame());
         provideTo(navigator, supplementName(), adoptPtr(supplement));
     }
     return supplement;
 }
 
-String NavigatorDoNotTrack::doNotTrack(Navigator* navigator)
+bool NavigatorPointerEvents::pointerEnabled(Navigator* navigator)
 {
-    return NavigatorDoNotTrack::from(navigator)->doNotTrack();
+    return NavigatorPointerEvents::from(navigator)->pointerEnabled();

[Rick Byers, 2013/08/07 13:46:51]

As discussed, I wouldn't put pointerEnabled in here yet - better to focus just
on maxTouchPoints.

 }
 
-String NavigatorDoNotTrack::doNotTrack()
+bool NavigatorPointerEvents::pointerEnabled()
 {
-    return frame() ? frame()->loader()->client()->doNotTrackValue() : String();
+    return false;
+}
+
+long NavigatorPointerEvents::maxTouchPoints(Navigator* navigator)
+{
+    return NavigatorPointerEvents::from(navigator)->maxTouchPoints();
+}
+
+long NavigatorPointerEvents::maxTouchPoints()
+{
+#if OS(WINDOWS)
+    return GetSystemMetrics(SM_MAXIMUMTOUCHES);

[Rick Byers, 2013/08/07 13:46:51]

I suspect this won't work in the sandbox, and it really should be provided by
the browser anyway.  You probably want to plumb it through WebSettings like
device_supports_touch.  Alternately, perhaps we should better handle touch
screens coming and going during the life of a page (eg. USB KVM scenarios), in
which case you may need to have a notification of when it changes (similar to,
eg., screen resolution).

+#else
+    return 0;

[Rick Byers, 2013/08/07 13:46:51]

On platforms where we don't know the answer it's better not to expose the API
then to return a potentially incorrect value.  This might mean we should have a
RuntimeEnabledFeature for this as for touch-action (which you'd need anyway if
you don't get simultaneous approval to implement and ship).

+#endif
 }
 
 } // namespace WebCore