Disable environment variable override of API keys on official builds.

google_apis/google_api_keys.cc

Index: google_apis/google_api_keys.cc
diff --git a/google_apis/google_api_keys.cc b/google_apis/google_api_keys.cc
index ab92d1e4dccf7420e8c0b72b49b8f8343c995016..015b254b5494615b540d798ee3be0791c09c0db4 100644
--- a/google_apis/google_api_keys.cc
+++ b/google_apis/google_api_keys.cc
@@ -246,7 +246,8 @@ class APIKeyCache {
   // Gets a value for a key.  In priority order, this will be the value
   // provided via a command-line switch, the value provided via an
   // environment variable, or finally a value baked into the build.
-  // |command_line_switch| may be NULL.
+  // |command_line_switch| may be NULL. Official Google Chrome builds will not
+  // use the value provided by an environment variable.
   static std::string CalculateKeyValue(const char* baked_in_value,
                                        const char* environment_variable_name,
                                        const char* command_line_switch,
@@ -265,11 +266,17 @@ class APIKeyCache {
               << " with value " << key_value << " from Info.plist.";
     }
 #endif
+
+#if !defined(GOOGLE_CHROME_BUILD)
+    // Don't allow using the environment to override API keys for official
+    // Google Chrome builds. There have been reports of mangled environments
+    // affecting users (crbug.com/710575).
     if (environment->GetVar(environment_variable_name, &temp)) {
       key_value = temp;
       VLOG(1) << "Overriding API key " << environment_variable_name
               << " with value " << key_value << " from environment variable.";
     }
+#endif
 
     if (command_line_switch && command_line->HasSwitch(command_line_switch)) {
       key_value = command_line->GetSwitchValueASCII(command_line_switch);