Fix memory leak in PrerenderDispatcher.

Make the PrerenderingInterface into a scoped pointer.

BUG=127953


Review URL: https://chromiumcodereview.appspot.com/10391134

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@138494 0039d316-1c4b-4281-b951-d872f2087c98

chrome/renderer/prerender/prerender_dispatcher.cc

@@ -12,11 +12,14 @@
 
 namespace prerender {
 
-PrerenderDispatcher::PrerenderDispatcher() {
-  WebKit::WebPrerenderingSupport::initialize(new PrerenderingSupport());
+PrerenderDispatcher::PrerenderDispatcher()
+    : prerendering_support_(new PrerenderingSupport()) {
+  WebKit::WebPrerenderingSupport::initialize(prerendering_support_.get());
 }
 
 PrerenderDispatcher::~PrerenderDispatcher() {
+  if (prerendering_support_.get())
+    WebKit::WebPrerenderingSupport::shutdown();
 }
 
 bool PrerenderDispatcher::IsPrerenderURL(const GURL& url) const {

chrome/renderer/prerender/prerender_dispatcher.h

@@ -9,15 +9,20 @@
 #include <map>
 
 #include "base/compiler_specific.h"
+#include "base/memory/scoped_ptr.h"
 #include "content/public/renderer/render_process_observer.h"
 
 class GURL;
 
 namespace prerender {
 
+class PrerenderingSupport;
+
 // PrerenderDispatcher keeps track of which URLs are being prerendered. There
 // is only one PrerenderDispatcher per render process, and it will only be
-// aware of prerenders that are triggered by this render process.
+// aware of prerenders that are triggered by this render process.  As well,
+// it holds on to other objects that must exist once per-renderer process,
+// such as the PrerenderingSupport.
 class PrerenderDispatcher : public content::RenderProcessObserver {
  public:
   PrerenderDispatcher();
@@ -34,6 +39,10 @@ class PrerenderDispatcher : public content::RenderProcessObserver {
 
   typedef std::map<GURL, int> PrerenderMap;
   PrerenderMap prerender_urls_;
+
+  // There is one PrerenderingSupport object per renderer, and it provides
+  // the interface to prerendering to the WebKit platform.
+  scoped_ptr<PrerenderingSupport> prerendering_support_;
 };
 
 }  // namespace prerender

tools/valgrind/memcheck/suppressions.txt

@@ -5753,14 +5753,6 @@
    fun:_ZN3gfx9JPEGCodec6DecodeEPKhm
    fun:_ZN7history33HistoryBackendTest_DeleteAll_Test8TestBodyEv
 }
-{
-   bug_127953
-   Memcheck:Leak
-   fun:_Znw*
-   fun:_ZN9prerender19PrerenderDispatcherC1Ev
-   fun:_ZN6chrome27ChromeContentRendererClient19RenderThreadStartedEv
-   fun:_ZN16RenderThreadImpl4InitEv
-}
 {
    bug_128145a
    Memcheck:Leak