Store Origin Trials public key in browser prefs

chrome/common/pref_names.cc

Index: chrome/common/pref_names.cc
diff --git a/chrome/common/pref_names.cc b/chrome/common/pref_names.cc
index 54307fa27d2d3826c8ce96a118672b187f5b8c63..a6ed88811f0cfa304878e0abe6a60f4bce46815c 100644
--- a/chrome/common/pref_names.cc
+++ b/chrome/common/pref_names.cc
@@ -2213,4 +2213,8 @@ const char kMediaRouterFirstRunFlowAcknowledged[] =
     "media_router.firstrunflow.acknowledged";
 #endif
 
+// The base64-encoded representation of the public key to use to validate origin
+// trial token signatures.
+const char kOriginTrialPublicKey[] = "origin_trials.public_key";
+
 }  // namespace prefs