Add disabled origin trial feature list

chrome/common/origin_trials/origin_trial_key_manager.cc

Index: chrome/common/origin_trials/origin_trial_key_manager.cc
diff --git a/chrome/common/origin_trials/origin_trial_key_manager.cc b/chrome/common/origin_trials/origin_trial_key_manager.cc
index 12467d29e0300b0297cfa816715ff086e5894c25..42df061f284cda738dc5d4d8ab97168804b14527 100644
--- a/chrome/common/origin_trials/origin_trial_key_manager.cc
+++ b/chrome/common/origin_trials/origin_trial_key_manager.cc
@@ -6,7 +6,10 @@
 
 #include <stdint.h>
 
+#include <vector>
+
 #include "base/base64.h"
+#include "base/strings/string_split.h"
 
 // This is the default public key used for validating signatures.
 // TODO(iclelland): Provide a mechanism to allow for multiple signing keys.
@@ -38,3 +41,17 @@ bool OriginTrialKeyManager::SetPublicKeyFromASCIIString(
 base::StringPiece OriginTrialKeyManager::GetPublicKey() const {
   return base::StringPiece(public_key_);
 }
+
+bool OriginTrialKeyManager::SetDisabledFeatures(
+    const std::string& disabled_feature_list) {
+  std::vector<std::string> features =

[Sorin Jianu, 2016/06/07 17:20:24]

can be const.

[iclelland, 2016/06/08 13:37:56]

Done.

+      base::SplitString(disabled_feature_list, "|", base::TRIM_WHITESPACE,
+                        base::SPLIT_WANT_NONEMPTY);
+  for (std::string feature : features)

[Sorin Jianu, 2016/06/07 17:20:24]

maybe use ref to const or const auto& for the range loop.

[iclelland, 2016/06/08 13:37:56]

Done.

+    disabled_features_.insert(feature);

[chasej, 2016/06/07 15:51:31]

Is this intended to append to the existing set of disabled features? From the
SetXXX naming, I would expect this method to replace any existing contents.

[iclelland, 2016/06/08 13:37:56]

That's a good point. It should probably clear the original list, if any. I don't
see any reason to require it to retain that. Done.

+  return true;
+}
+
+bool OriginTrialKeyManager::IsFeatureDisabled(base::StringPiece feature) {
+  return disabled_features_.count(feature.as_string()) > 0;
+}