Bug 1066166 - Add localized tooltip captions for each tab button on the Loop panel. r=jaws

browser/components/loop/content/js/panel.js

@@ -67,6 +67,7 @@ loop.panel = (function(_, mozL10n) {
             React.createElement("li", {className: cx({selected: isSelected}), 
                 key: i, 
                 "data-tab-name": tabName, 
+                title: mozL10n.get(tabName + "_tab_button_tooltip"), 
                 onClick: this.handleSelectTab})
           );
         }

browser/components/loop/content/js/panel.jsx

@@ -67,6 +67,7 @@ loop.panel = (function(_, mozL10n) {
             <li className={cx({selected: isSelected})}
                 key={i}
                 data-tab-name={tabName}
+                title={mozL10n.get(tabName + "_tab_button_tooltip")}
                 onClick={this.handleSelectTab} />
           );
         }

browser/locales/en-US/chrome/browser/loop/loop.properties

@@ -8,6 +8,9 @@
 ## should remain "Firefox Hello" for all locales.
 clientShortname2=Firefox Hello
 
+rooms_tab_button_tooltip=Conversations
+contacts_tab_button_tooltip=Contacts
+
 ## LOCALIZATION_NOTE(first_time_experience.title): clientShortname will be
 ## replaced by the brand name
 first_time_experience_title={{clientShortname}} — Join the conversation