Improve error message for insecure 'content_security_policy' manifest entries.

chrome/common/extensions/extension_manifest_constants.cc

Index: chrome/common/extensions/extension_manifest_constants.cc
diff --git a/chrome/common/extensions/extension_manifest_constants.cc b/chrome/common/extensions/extension_manifest_constants.cc
index ad5e4463af89a82b7a6fb50802c4e549f287ef97..beeae9b4ba0f2e4ab0c6d545d6cbbd3670ee67ce 100644
--- a/chrome/common/extensions/extension_manifest_constants.cc
+++ b/chrome/common/extensions/extension_manifest_constants.cc
@@ -452,6 +452,13 @@ const char kInvalidWebURLs[] =
     "Invalid value for 'app.urls'.";
 const char kInvalidZipHash[] =
     "Required key 'zip_hash' is missing or invalid.";
+const char kInsecureContentSecurityPolicy[] =
+    "Invalid value for 'content_security_policy': The 'script-src' and"
+    " 'object-src' directives can only whitelist secure resources. You may"
+    " include any of the following sources: \"'self'\", \"http://127.0.0.1\","
+    " \"http://localhost\", or any \"https://\" or \"chrome-extension://\""
+    " origin. For more information, see"
+    " http://developer.chrome.com/extensions/contentSecurityPolicy.html";
 const char kLaunchPathAndExtentAreExclusive[] =
     "The 'app.launch.local_path' and 'app.urls' keys cannot both be set.";
 const char kLaunchPathAndURLAreExclusive[] =