Bug 1258925 - [e10s] Browser window is resized when click. r=gabor

Adds a new IPC message to the PBrowser protocol exposing
the number of tabs in the current window to the content
process. This allows the content process to reject window.resize*
calls in cases where there is more than one tab in the
window.

--HG--
extra : histedit_source : dfa6b7b71882a1583cbbe90c2a7327cb212ed15d

browser/base/content/browser.js

@@ -4157,6 +4157,10 @@ var XULBrowserWindow = {
     elt.hidePopup();
   },
 
+  getTabCount: function () {
+    return gBrowser.tabs.length;
+  },
+
   updateStatusField: function () {
     var text, type, types = ["overLink"];
     if (this._busyUI)

dom/base/nsGlobalWindow.cpp

@@ -6434,13 +6434,23 @@ nsGlobalWindow::CanMoveResizeWindows(bool aCallerIsChrome)
     }
 
     // Ignore the request if we have more than one tab in the window.
-    nsCOMPtr<nsIDocShellTreeOwner> treeOwner = GetTreeOwner();
-    if (treeOwner) {
-      uint32_t itemCount;
-      if (NS_SUCCEEDED(treeOwner->GetTargetableShellCount(&itemCount)) &&
-          itemCount > 1) {
-        return false;
+    uint32_t itemCount = 0;
+    if (XRE_IsContentProcess()) {
+      nsCOMPtr<nsIDocShell> docShell = GetDocShell();
+      if (docShell) {
+        nsCOMPtr<nsITabChild> child = docShell->GetTabChild();
+        if (child) {
+          child->SendGetTabCount(&itemCount);
+        }
       }
+    } else {
+      nsCOMPtr<nsIDocShellTreeOwner> treeOwner = GetTreeOwner();
+      if (treeOwner) {
+        treeOwner->GetTargetableShellCount(&itemCount);
+      }
+    }
+    if (itemCount > 1) {
+      return false;
     }
   }
 

dom/interfaces/base/nsITabChild.idl

@@ -19,6 +19,8 @@ interface nsITabChild : nsISupports
 
   [notxpcom] void sendRequestFocus(in boolean canFocus);
 
+  [notxpcom] void sendGetTabCount(out uint32_t tabCount);
+
   [noscript, notxpcom] void enableDisableCommands(in AString action,
                                                   in CommandsArrayRef enabledCommands,
                                                   in CommandsArrayRef disabledCommands);

dom/ipc/PBrowser.ipdl

@@ -470,6 +470,8 @@ parent:
                                    bool aLongTap,
                                    uint64_t aObserverId);
     async ClearNativeTouchSequence(uint64_t aObserverId);
+
+    sync GetTabCount() returns (uint32_t value);
 child:
     async NativeSynthesisResponse(uint64_t aObserverId, nsCString aResponse);
 

dom/ipc/TabChild.cpp

@@ -2727,6 +2727,12 @@ TabChild::SendRequestFocus(bool aCanFocus)
   PBrowserChild::SendRequestFocus(aCanFocus);
 }
 
+void
+TabChild::SendGetTabCount(uint32_t* tabCount)
+{
+  PBrowserChild::SendGetTabCount(tabCount);
+}
+
 void
 TabChild::EnableDisableCommands(const nsAString& aAction,
                                 nsTArray<nsCString>& aEnabledCommands,

dom/ipc/TabParent.cpp

@@ -3244,6 +3244,20 @@ TabParent::AudioChannelChangeNotification(nsPIDOMWindowOuter* aWindow,
   }
 }
 
+bool
+TabParent::RecvGetTabCount(uint32_t* aValue)
+{
+  nsCOMPtr<nsIXULBrowserWindow> xulBrowserWindow = GetXULBrowserWindow();
+  NS_ENSURE_TRUE(xulBrowserWindow, false);
+
+  uint32_t tabCount;
+  nsresult rv = xulBrowserWindow->GetTabCount(&tabCount);
+  NS_ENSURE_SUCCESS(rv, false);
+
+  *aValue = tabCount;
+  return true;
+}
+
 NS_IMETHODIMP
 FakeChannel::OnAuthAvailable(nsISupports *aContext, nsIAuthInformation *aAuthInfo)
 {

dom/ipc/TabParent.h

@@ -582,6 +582,8 @@ protected:
                                  const int32_t& aX, const int32_t& aY,
                                  const int32_t& aCx, const int32_t& aCy) override;
 
+  virtual bool RecvGetTabCount(uint32_t* aValue) override;
+
   virtual bool RecvAudioChannelActivityNotification(const uint32_t& aAudioChannel,
                                                     const bool& aActive) override;
 

xpfe/appshell/nsIXULBrowserWindow.idl

@@ -67,5 +67,10 @@ interface nsIXULBrowserWindow : nsISupports
    */
   void showTooltip(in long x, in long y, in AString tooltip, in AString direction);
   void hideTooltip();
+
+  /**
+   * Return the number of tabs in this window.
+   */
+  uint32_t getTabCount();
 };