Suppress tabs permission warning if there is already a browsingHistory warning.

chrome/common/extensions/permissions/chrome_permission_message_provider.cc

Index: chrome/common/extensions/permissions/chrome_permission_message_provider.cc
diff --git a/chrome/common/extensions/permissions/chrome_permission_message_provider.cc b/chrome/common/extensions/permissions/chrome_permission_message_provider.cc
index f0c415d5f79b70d1c8f4d86d16a28c3d99da7408..84c25188d1fe56c736be872997029d2423a5557a 100644
--- a/chrome/common/extensions/permissions/chrome_permission_message_provider.cc
+++ b/chrome/common/extensions/permissions/chrome_permission_message_provider.cc
@@ -73,6 +73,17 @@ PermissionMessages::iterator FindMessageByID(PermissionMessages& messages,
   return messages.end();
 }
 
+void SuppressMessage(PermissionMessages& messages,
+                     int suppressing_message,
+                     int suppressed_message) {
+  PermissionMessages::iterator suppressed =
+      FindMessageByID(messages, suppressed_message);
+  if (suppressed != messages.end() &&
+      FindMessageByID(messages, suppressing_message) != messages.end()) {
+    messages.erase(suppressed);
+  }
+}
+
 }  // namespace
 
 ChromePermissionMessageProvider::ChromePermissionMessageProvider() {
@@ -104,16 +115,14 @@ PermissionMessages ChromePermissionMessageProvider::GetPermissionMessages(
   messages.insert(messages.end(), manifest_permission_msgs.begin(),
                   manifest_permission_msgs.end());
 
-  // Special hack: bookmarks permission message supersedes override bookmarks UI
-  // permission message if both permissions are specified.
-  PermissionMessages::iterator override_bookmarks_ui =
-      FindMessageByID(messages, PermissionMessage::kOverrideBookmarksUI);
-  if (override_bookmarks_ui != messages.end() &&
-      FindMessageByID(messages, PermissionMessage::kBookmarks) !=
-          messages.end()) {
-    messages.erase(override_bookmarks_ui);
-  }
-
+  // Some warnings are more generic and/or powerful and superseed other
+  // warnings. In that case, suppress the superseeded warning.
+  SuppressMessage(messages,
+                  PermissionMessage::kBookmarks,
+                  PermissionMessage::kOverrideBookmarksUI);
+  SuppressMessage(messages,
+                  PermissionMessage::kBrowsingHistory,
+                  PermissionMessage::kTabs);
   return messages;
 }