Add details (where missing) for histograms and remove a few that are not worth providing more details for.

BUG=None

Review URL: https://codereview.chromium.org/270363006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@270409 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/chrome/browser/extensions/dev_mode_bubble_controller.cc b/chrome/browser/extensions/dev_mode_bubble_controller.cc
index db7e36c..b8b0f0e 100644
--- a/chrome/browser/extensions/dev_mode_bubble_controller.cc
+++ b/chrome/browser/extensions/dev_mode_bubble_controller.cc
@@ -105,13 +105,13 @@
 
 void DevModeBubbleDelegate::LogExtensionCount(size_t count) {
   UMA_HISTOGRAM_COUNTS_100(
-      "DevModeExtensionBubble.ExtensionsInDevModeCount", count);
+      "ExtensionBubble.ExtensionsInDevModeCount", count);
 }
 
 void DevModeBubbleDelegate::LogAction(
     ExtensionMessageBubbleController::BubbleAction action) {
   UMA_HISTOGRAM_ENUMERATION(
-      "DevModeExtensionBubble.UserSelection",
+      "ExtensionBubble.DevModeUserSelection",
       action, ExtensionMessageBubbleController::ACTION_BOUNDARY);
 }