Bug 1207741 - Remove gfxIntSize. r=nical.

gfxIntSize is just a typedef of gfx::IntSize, so this is very mechanical. The
only tricky part is deciding for each occurrence whether to replace it with
IntSize, gfx::IntSize or mozilla::gfx::IntSize; in all cases I went with the
shortest one that worked given the existing "using namespace" declarations.

widget/android/nsScreenManagerAndroid.cpp

@@ -29,7 +29,7 @@ nsScreenAndroid::GetId(uint32_t *outId)
 NS_IMETHODIMP
 nsScreenAndroid::GetRect(int32_t *outLeft, int32_t *outTop, int32_t *outWidth, int32_t *outHeight)
 {
-    gfxIntSize sz = nsWindow::GetAndroidScreenBounds();
+    gfx::IntSize sz = nsWindow::GetAndroidScreenBounds();
 
     *outLeft = 0;
     *outTop = 0;