Bug 1498522 - Change the 'Highlight All' keybinding back to using 'a', instead of the new 'l' on all platforms, except OSX. r=Gijs,flod

Differential Revision: https://phabricator.services.mozilla.com/D8528

--HG--
extra : moz-landing-system : lando

toolkit/content/widgets/findbar.js

@@ -34,7 +34,7 @@ class MozFindbar extends XULElement {
           <toolbarbutton anonid="find-previous" class="findbar-find-previous tabbable" data-l10n-attrs="tooltiptext" data-l10n-id="findbar-previous" oncommand="onFindAgainCommand(true);" disabled="true" />
           <toolbarbutton anonid="find-next" class="findbar-find-next tabbable" data-l10n-id="findbar-next" oncommand="onFindAgainCommand(false);" disabled="true" />
         </hbox>
-        <toolbarbutton anonid="highlight" class="findbar-highlight findbar-button tabbable" data-l10n-id="findbar-highlight-all" oncommand="toggleHighlight(this.checked);" type="checkbox" />
+        <toolbarbutton anonid="highlight" class="findbar-highlight findbar-button tabbable" data-l10n-id="findbar-highlight-all2" oncommand="toggleHighlight(this.checked);" type="checkbox" />
         <toolbarbutton anonid="find-case-sensitive" class="findbar-case-sensitive findbar-button tabbable" data-l10n-id="findbar-case-sensitive" oncommand="_setCaseSensitivity(this.checked ? 1 : 0);" type="checkbox" />
         <toolbarbutton anonid="find-entire-word" class="findbar-entire-word findbar-button tabbable" data-l10n-id="findbar-entire-word" oncommand="toggleEntireWord(this.checked);" type="checkbox" />
         <label anonid="match-case-status" class="findbar-find-fast" />

toolkit/locales/en-US/toolkit/main-window/findbar.ftl

@@ -12,9 +12,12 @@ findbar-previous =
 findbar-find-button-close =
     .tooltiptext = Close find bar
 
-findbar-highlight-all =
+findbar-highlight-all2 =
     .label = Highlight All
-    .accesskey = l
+    .accesskey = { PLATFORM() ->
+        [macos] l
+       *[other] a
+    }
     .tooltiptext = Highlight all occurrences of the phrase
 
 findbar-case-sensitive =