Bug 773998: Shut down app processes when the last browser closes. r=jlebar

dom/ipc/ContentParent.cpp

@@ -251,6 +251,49 @@ ContentParent::Init()
 #endif
 }
 
+void
+ContentParent::ShutDown()
+{
+    if (mIsAlive) {
+        // Close() can only be called once.  It kicks off the
+        // destruction sequence.
+        Close();
+    }
+    // NB: must MarkAsDead() here so that this isn't accidentally
+    // returned from Get*() while in the midst of shutdown.
+    MarkAsDead();
+}
+
+void
+ContentParent::MarkAsDead()
+{
+    if (!mAppManifestURL.IsEmpty()) {
+        if (gAppContentParents) {
+            gAppContentParents->Remove(mAppManifestURL);
+            if (!gAppContentParents->Count()) {
+                delete gAppContentParents;
+                gAppContentParents = NULL;
+            }
+        }
+    } else if (gNonAppContentParents) {
+        gNonAppContentParents->RemoveElement(this);
+        if (!gNonAppContentParents->Length()) {
+            delete gNonAppContentParents;
+            gNonAppContentParents = NULL;
+        }
+    }
+
+    if (gPrivateContent) {
+        gPrivateContent->RemoveElement(this);
+        if (!gPrivateContent->Length()) {
+            delete gPrivateContent;
+            gPrivateContent = NULL;
+        }
+    }
+
+    mIsAlive = false;
+}
+
 void
 ContentParent::OnChannelConnected(int32 pid)
 {
@@ -349,29 +392,7 @@ ContentParent::ActorDestroy(ActorDestroyReason why)
     if (mRunToCompletionDepth)
         mRunToCompletionDepth = 0;
 
-    if (!mAppManifestURL.IsEmpty()) {
-        gAppContentParents->Remove(mAppManifestURL);
-        if (!gAppContentParents->Count()) {
-            delete gAppContentParents;
-            gAppContentParents = NULL;
-        }
-    } else {
-        gNonAppContentParents->RemoveElement(this);
-        if (!gNonAppContentParents->Length()) {
-            delete gNonAppContentParents;
-            gNonAppContentParents = NULL;
-        }
-    }
-
-    if (gPrivateContent) {
-        gPrivateContent->RemoveElement(this);
-        if (!gPrivateContent->Length()) {
-            delete gPrivateContent;
-            gPrivateContent = NULL;
-        }
-    }
-
-    mIsAlive = false;
+    MarkAsDead();
 
     if (obs) {
         nsRefPtr<nsHashPropertyBag> props = new nsHashPropertyBag();
@@ -416,6 +437,19 @@ ContentParent::CreateTab(PRUint32 aChromeFlags, bool aIsBrowserFrame)
   return static_cast<TabParent*>(SendPBrowserConstructor(aChromeFlags, aIsBrowserFrame));
 }
 
+void
+ContentParent::NotifyTabDestroyed(PBrowserParent* aTab)
+{
+    // There can be more than one PBrowser for a given app process
+    // because of popup windows.  When the last one closes, shut
+    // us down.
+    if (IsForApp() && ManagedPBrowserParent().Length() == 1) {
+        MessageLoop::current()->PostTask(
+            FROM_HERE,
+            NewRunnableMethod(this, &ContentParent::ShutDown));
+    }
+}
+
 TestShellParent*
 ContentParent::CreateTestShell()
 {
@@ -493,6 +527,12 @@ ContentParent::IsAlive()
     return mIsAlive;
 }
 
+bool
+ContentParent::IsForApp()
+{
+    return !mAppManifestURL.IsEmpty();
+}
+
 bool
 ContentParent::RecvReadPrefsArray(InfallibleTArray<PrefTuple> *prefs)
 {

dom/ipc/ContentParent.h

@@ -68,6 +68,8 @@ public:
      * <iframe mozbrowser>.
      */
     TabParent* CreateTab(PRUint32 aChromeFlags, bool aIsBrowserFrame);
+    /** Notify that a tab was destroyed during normal operation. */
+    void NotifyTabDestroyed(PBrowserParent* aTab);
 
     TestShellParent* CreateTestShell();
     bool DestroyTestShell(TestShellParent* aTestShell);
@@ -77,6 +79,7 @@ public:
     bool RequestRunToCompletion();
 
     bool IsAlive();
+    bool IsForApp();
 
     void SetChildMemoryReporters(const InfallibleTArray<MemoryReport>& report);
 
@@ -107,6 +110,20 @@ private:
 
     void Init();
 
+    /**
+     * Mark this ContentParent as dead for the purposes of Get*().
+     * This method is idempotent.
+     */
+    void MarkAsDead();
+
+    /**
+     * Exit the subprocess and vamoose.  After this call IsAlive()
+     * will return false and this ContentParent will not be returned
+     * by the Get*() funtions.  However, the shutdown sequence itself
+     * may be asynchronous.
+     */
+    void ShutDown();
+
     virtual PBrowserParent* AllocPBrowser(const PRUint32& aChromeFlags, const bool& aIsBrowserFrame);
     virtual bool DeallocPBrowser(PBrowserParent* frame);
 

dom/ipc/TabParent.cpp

@@ -99,6 +99,14 @@ TabParent::Destroy()
   }
 }
 
+bool
+TabParent::Recv__delete__()
+{
+  ContentParent* cp = static_cast<ContentParent*>(Manager());
+  cp->NotifyTabDestroyed(this);
+  return true;
+}
+
 void
 TabParent::ActorDestroy(ActorDestroyReason why)
 {

dom/ipc/TabParent.h

@@ -164,7 +164,9 @@ protected:
                         const nsString& aJSON,
                         InfallibleTArray<nsString>* aJSONRetVal = nsnull);
 
-    void ActorDestroy(ActorDestroyReason why);
+    virtual bool Recv__delete__() MOZ_OVERRIDE;
+
+    virtual void ActorDestroy(ActorDestroyReason why) MOZ_OVERRIDE;
 
     virtual PIndexedDBParent* AllocPIndexedDB(const nsCString& aASCIIOrigin,
                                               bool* /* aAllowed */);