Bug 1044334 - Part 3: fix access to tabs_panel_footer in TabsPanel. r=lucasr

mobile/android/base/resources/layout/tabs_panel.xml

@@ -53,4 +53,9 @@
 
     </view>
 
+    <!-- To preserve the ID, even when building for pre-11. -->
+    <RelativeLayout android:id="@+id/tabs_panel_footer"
+                    android:layout_height="0dp"
+                    android:layout_width="0dp"
+                    android:visibility="gone"/>
 </merge>

mobile/android/base/tabs/TabsPanel.java

@@ -140,7 +140,12 @@ public class TabsPanel extends LinearLayout
         mPanelRemote = (PanelView) findViewById(R.id.remote_tabs);
         mPanelRemote.setTabsPanel(this);
 
-        mFooter = (RelativeLayout) findViewById(R.id.tabs_panel_footer);
+        // Only applies to v11+ in landscape.
+        // We ship a stub to avoid a compiler error when referencing the
+        // ID, so we conditionalize here.
+        if (Versions.feature11Plus) {
+            mFooter = (RelativeLayout) findViewById(R.id.tabs_panel_footer);
+        }
 
         mAddTab = (ImageButton) findViewById(R.id.add_tab);
         mAddTab.setOnClickListener(new Button.OnClickListener() {
@@ -425,8 +430,10 @@ public class TabsPanel extends LinearLayout
         mPanel.show();
 
         if (mCurrentPanel == Panel.REMOTE_TABS) {
-            if (mFooter != null)
+            // The footer is only defined in the sidebar, for landscape v11+ views.
+            if (mFooter != null) {
                 mFooter.setVisibility(View.GONE);
+            }
 
             mAddTab.setVisibility(View.INVISIBLE);
 
@@ -512,7 +519,8 @@ public class TabsPanel extends LinearLayout
             if (mVisible) {
                 ViewHelper.setTranslationX(mHeader, -tabsPanelWidth);
                 ViewHelper.setTranslationX(mTabsContainer, -tabsPanelWidth);
-                // The footer view is only present on the sidebar
+
+                // The footer view is only present on the sidebar, v11+.
                 ViewHelper.setTranslationX(mFooter, -tabsPanelWidth);
             }
             final int translationX = (mVisible ? 0 : -tabsPanelWidth);