Add deprecation message for CSSXGetComputedStyleQueries.

third_party/WebKit/Source/core/frame/UseCounter.cpp

Index: third_party/WebKit/Source/core/frame/UseCounter.cpp
diff --git a/third_party/WebKit/Source/core/frame/UseCounter.cpp b/third_party/WebKit/Source/core/frame/UseCounter.cpp
index 63f6db30154e4f85b89a734437fffdeaac690f28..c12b5b2df0640d549daac7aac17f73bcd0978a9b 100644
--- a/third_party/WebKit/Source/core/frame/UseCounter.cpp
+++ b/third_party/WebKit/Source/core/frame/UseCounter.cpp
@@ -957,6 +957,9 @@ String UseCounter::deprecationMessage(Feature feature)
     case MediaStreamTrackGetSources:
         return "MediaStreamTrack.getSources is deprecated. See https://www.chromestatus.com/feature/4765305641369600 for more details.";
 
+    case CSSXGetComputedStyleQueries:
+        return "'getComputedStyle(e).cssXx' (except .cssFloat) is deprecated and will be removed in M50, around April 2016. Please use 'getComputedStyle(e).xx' instead.";
+
     // Features that aren't deprecated don't have a deprecation message.
     default:
         return String();