Bug 1369794 - Fit clickable area of onboarding icon with icon size. r=mossop

MozReview-Commit-ID: 7PzGPHqKDms

--HG--
extra : rebase_source : c2ddf8e11d84f852dcc905361408af219582c1eb

browser/extensions/onboarding/content/onboarding.css

@@ -24,8 +24,8 @@
 }
 
 #onboarding-overlay-icon {
-  width: 52px;
-  height: 40px;
+  width: 36px;
+  height: 29px;
   position: absolute;
   cursor: pointer;
   top: 30px;