Add a date/details link to FileError deprecation warning

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

Index: third_party/WebKit/Source/core/frame/Deprecation.cpp
diff --git a/third_party/WebKit/Source/core/frame/Deprecation.cpp b/third_party/WebKit/Source/core/frame/Deprecation.cpp
index 779fb04c03bfdd31b5e3c7d071e629f9e62da7ed..d9f49c2a9e6db88095327af1e50251c4d84ada23 100644
--- a/third_party/WebKit/Source/core/frame/Deprecation.cpp
+++ b/third_party/WebKit/Source/core/frame/Deprecation.cpp
@@ -178,7 +178,7 @@ String Deprecation::deprecationMessage(UseCounter::Feature feature)
         return replacedBy("'console.markTimeline'", "'console.timeStamp'");
 
     case UseCounter::FileError:
-        return "FileError is deprecated. Please use the 'name' or 'message' attributes of DOMError rather than 'code'.";
+        return String::format("'FileError is deprecated and will be removed in %s. Please use the 'name' or 'message' attributes of the error rather than 'code'. See https://www.chromestatus.com/features/%s for more details.", milestoneString(53), "6687420359639040");

[foolip, 2016/06/03 06:48:46]

You can merge 6687420359639040 into the first string.

[jsbell, 2016/07/13 17:20:26]

Done.

 
     case UseCounter::CSSStyleSheetInsertRuleOptionalArg:
         return "Calling CSSStyleSheet.insertRule() with one argument is deprecated. Please pass the index argument as well: insertRule(x, 0).";