Bug 1055427 - Add KillChild() method to nsIMessageManager. r=sicking

Patch originally from bug 1000313.

content/base/public/nsIMessageManager.idl

@@ -405,9 +405,10 @@ interface nsIFrameScriptLoader : nsISupports
   jsval getDelayedFrameScripts();
 };
 
-[scriptable, builtinclass, uuid(ad57800b-ff21-4e2f-91d3-e68615ae8afe)]
+[scriptable, builtinclass, uuid(637e8538-4f8f-4a3d-8510-e74386233e19)]
 interface nsIProcessChecker : nsISupports
 {
+  bool killChild();
 
   /**
    * Return true if the "remote" process has |aPermission|.  This is

content/base/src/nsFrameMessageManager.cpp

@@ -803,6 +803,18 @@ nsFrameMessageManager::Atob(const nsAString& aAsciiString,
 
 // nsIProcessChecker
 
+NS_IMETHODIMP
+nsFrameMessageManager::KillChild(bool *aValid)
+{
+  if (!mCallback) {
+    *aValid = false;
+    return NS_ERROR_NOT_AVAILABLE;
+  }
+
+  *aValid = mCallback->KillChild();
+  return NS_OK;
+}
+
 nsresult
 nsFrameMessageManager::AssertProcessInternal(ProcessCheckerType aType,
                                              const nsAString& aCapability,

content/base/src/nsFrameMessageManager.h

@@ -98,6 +98,12 @@ public:
     return false;
   }
 
+  virtual bool KillChild()
+  {
+    // By default, does nothing.
+    return false;
+  }
+
 protected:
   bool BuildClonedMessageDataForParent(nsIContentParent* aParent,
                                        const StructuredCloneData& aData,

dom/ipc/ContentParent.cpp

@@ -3746,6 +3746,13 @@ ContentParent::CheckAppHasStatus(unsigned short aStatus)
     return AssertAppHasStatus(this, aStatus);
 }
 
+bool
+ContentParent::KillChild()
+{
+  KillHard();
+  return true;
+}
+
 PBlobParent*
 ContentParent::SendPBlobConstructor(PBlobParent* aActor,
                                     const BlobConstructorParams& aParams)

dom/ipc/ContentParent.h

@@ -161,6 +161,7 @@ public:
     virtual bool CheckManifestURL(const nsAString& aManifestURL) MOZ_OVERRIDE;
     virtual bool CheckAppHasPermission(const nsAString& aPermission) MOZ_OVERRIDE;
     virtual bool CheckAppHasStatus(unsigned short aStatus) MOZ_OVERRIDE;
+    virtual bool KillChild() MOZ_OVERRIDE;
 
     /** Notify that a tab is beginning its destruction sequence. */
     void NotifyTabDestroying(PBrowserParent* aTab);