Deprecate fetching stylesheets with unsupported type

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 fb5b10670ed70e5eba1e36336e580c56851bf0de..7f7fe5df26d2050caf8949a1035e09849bb1b8b7 100644
--- a/third_party/WebKit/Source/core/frame/UseCounter.cpp
+++ b/third_party/WebKit/Source/core/frame/UseCounter.cpp
@@ -972,6 +972,9 @@ String UseCounter::deprecationMessage(Feature feature)
     case ObjectObserve:
         return willBeRemoved("'Object.observe'", 50, "6147094632988672");
 
+    case NonCSSStyleSheetType:
+        return String::format("Using stylesheet links with types other than 'text/css' is deprecated and will be removed in %s.", milestoneString(50));
+
     // Features that aren't deprecated don't have a deprecation message.
     default:
         return String();