Rename WebCore namespace to blink in Platform

Source/platform/PlatformMouseEvent.h

Index: Source/platform/PlatformMouseEvent.h
diff --git a/Source/platform/PlatformMouseEvent.h b/Source/platform/PlatformMouseEvent.h
index 76292fa996ac66054ff4d1138e0126b1a51f940c..4a4b8a95ee4539a6f39e03ce151b885fb093e07c 100644
--- a/Source/platform/PlatformMouseEvent.h
+++ b/Source/platform/PlatformMouseEvent.h
@@ -29,7 +29,7 @@
 #include "platform/PlatformEvent.h"
 #include "platform/geometry/IntPoint.h"
 
-namespace WebCore {
+namespace blink {
 
 // These button numbers match the ones used in the DOM API, 0 through 2, except for NoButton which isn't specified.
 enum MouseButton { NoButton = -1, LeftButton, MiddleButton, RightButton };
@@ -102,6 +102,6 @@ protected:
     unsigned m_modifierFlags;
 };
 
-} // namespace WebCore
+} // namespace blink
 
 #endif // PlatformMouseEvent_h