Bug 1286523 - fix HTML autocomplete overflow issue;r=bgrins

When the autocomplete popup has a scrollbar, the rightmost part
of the suggestions is hidden when using RTL locale.

XUL autocompletes (using the richlistbox) were always displaying the
suggestions using LTR. I couldn't find any CSS rule enforcing this, so
I assume this was a default behavior of the richlist box.
This patch restores the same behavior as before.

MozReview-Commit-ID: 9AcMxEe6tuL

--HG--
extra : rebase_source : 9329892b3d387739ffc9c53d3c89b3a30e8833ff

devtools/client/themes/common.css

@@ -68,15 +68,13 @@
   padding: 2px;
 }
 
-.devtools-autocomplete-listbox > scrollbox {
-  padding: 2px;
-}
-
 .devtools-autocomplete-listbox .autocomplete-item {
   width: 100%;
   background-color: transparent;
   border-radius: 4px;
   padding: 1px 0;
+  /* Force text-align even in RTL locales to ensure a correct display of the popup */
+  text-align: left;
 }
 
 .devtools-autocomplete-listbox .autocomplete-selected {