Added check for behavior feature existense

extensions/common/features/feature_provider.h

Index: extensions/common/features/feature_provider.h
diff --git a/extensions/common/features/feature_provider.h b/extensions/common/features/feature_provider.h
index ae975137b508e845f81fca7498652006bf2bcaa3..ce575f27061b00d6f60ac2df80a02227e740e847 100644
--- a/extensions/common/features/feature_provider.h
+++ b/extensions/common/features/feature_provider.h
@@ -13,6 +13,7 @@
 
 namespace extensions {
 
+class Extension;

[benwells, 2016/04/14 06:36:15]

It's nice that this file doesn't depend on Extension. It's also a bit weird now
that the behavior features don't follow the same pattern of the other features.

Can you revert the changes in this file, but ad a comment above Get*Feature that
the features can be null if JSON files are corrupted, and just put null checks
in the callsites to GetBehaviorFeature?

 class Feature;
 
 using FeatureMap = std::map<std::string, scoped_ptr<Feature>>;
@@ -42,7 +43,12 @@ class FeatureProvider {
   static const Feature* GetAPIFeature(const std::string& name);
   static const Feature* GetManifestFeature(const std::string& name);
   static const Feature* GetPermissionFeature(const std::string& name);
-  static const Feature* GetBehaviorFeature(const std::string& name);
+
+  // Check if behavior feature exists and is available for extension.
+  // Feature existence should be checked as sometimes JSONReader fails to read
+  // resource file correctly. See http://crbug.com/176381
+  static bool BehaviorFeatureIsAvailable(const std::string& name,
+                                         const Extension* extension);
 
   //
   // Instance methods.