Bug 696602 - Active tab not shown in tab strip on return from Panorama r=tim

browser/base/content/tabbrowser.xml

@@ -1963,6 +1963,8 @@
             else
               this.showTab(tab);
           }, this);
+
+          this.tabContainer.mTabstrip.ensureElementIsVisible(this.selectedTab, false);
         ]]>
         </body>
       </method>

browser/components/tabview/test/Makefile.in

@@ -164,6 +164,7 @@ _BROWSER_FILES = \
                  browser_tabview_bug685476.js \
                  browser_tabview_bug685692.js \
                  browser_tabview_bug686654.js \
+                 browser_tabview_bug696602.js \
                  browser_tabview_bug697390.js \
                  browser_tabview_bug705621.js \
                  browser_tabview_bug706430.js \

browser/components/tabview/test/browser_tabview_bug696602.js

@@ -0,0 +1,51 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+let win;
+
+function test() {
+  waitForExplicitFinish();
+
+  newWindowWithTabView(function(newWin) {
+    win = newWin;
+
+    registerCleanupFunction(function() {
+      win.close();
+    });
+
+    let cw = win.TabView.getContentWindow();
+    let groupItemOne = cw.GroupItems.groupItems[0];
+    let groupItemTwo = createGroupItemWithBlankTabs(win, 300, 300, 20, 10);
+
+    is(win.gBrowser.tabContainer.getAttribute("overflow"), "true",
+       "The tabstrip is overflow");
+
+    is(groupItemOne.getChildren().length, 10, "Group one has 10 tabs");
+    is(groupItemTwo.getChildren().length, 10, "Group two has 10 tabs");
+
+    checkSelectedTabVisible("two", function() {
+      showTabView(function() {
+        checkSelectedTabVisible("one", finish);
+        groupItemOne.getChild(9).zoomIn();
+      }, win);
+    });
+    groupItemTwo.getChild(9).zoomIn();
+  }, function(newWin) {
+    for (let i = 0; i < 9; i++)
+      newWin.gBrowser.addTab();
+  });
+}
+
+function isSelectedTabVisible() {
+  let tabstrip = win.gBrowser.tabContainer.mTabstrip;
+  let scrollRect = tabstrip.scrollClientRect;
+  let tab = win.gBrowser.selectedTab.getBoundingClientRect();
+
+  return (scrollRect.left <= tab.left && tab.right <= scrollRect.right);
+}
+
+function checkSelectedTabVisible(groupName, callback) {
+  whenTabViewIsHidden(function() {
+    ok(isSelectedTabVisible(), "Group " + groupName + " selected tab is visible");
+    callback();
+  }, win);
+}

browser/components/tabview/ui.js

@@ -152,6 +152,10 @@ let UI = {
   // Used to keep track of the last opened tab.
   _lastOpenedTab: null,
 
+  // Variable: _originalSmoothScroll
+  // Used to keep track of the tab strip smooth scroll value.
+  _originalSmoothScroll: null,
+
   // ----------
   // Function: toString
   // Prints [UI] for debug use
@@ -514,6 +518,11 @@ let UI = {
 
     this._isChangingVisibility = true;
 
+    // store tab strip smooth scroll value and disable it.
+    let tabStrip = gBrowser.tabContainer.mTabstrip;
+    this._originalSmoothScroll = tabStrip.smoothScroll;
+    tabStrip.smoothScroll = false;
+
     // initialize the direction of the page
     this._initPageDirection();
 
@@ -609,6 +618,7 @@ let UI = {
     gBrowser.selectedBrowser.focus();
 
     gBrowser.updateTitlebar();
+    gBrowser.tabContainer.mTabstrip.smoothScroll = this._originalSmoothScroll;
 #ifdef XP_MACOSX
     this.setTitlebarColors(false);
 #endif