Fix crash when a download is requested for an outdated plugin.

chrome/browser/plugins/plugin_installer.cc

Index: chrome/browser/plugins/plugin_installer.cc
diff --git a/chrome/browser/plugins/plugin_installer.cc b/chrome/browser/plugins/plugin_installer.cc
index 678addd6dba53ff6e761191cc90006961d6002e9..d109f9f7f8b1b3fb2193228a89d4a0436a8f4b12 100644
--- a/chrome/browser/plugins/plugin_installer.cc
+++ b/chrome/browser/plugins/plugin_installer.cc
@@ -37,7 +37,7 @@ using content::ResourceDispatcherHost;
 namespace {
 
 void BeginDownload(
-    const GURL& url,
+    GURL url,
     content::ResourceContext* resource_context,
     int render_process_host_id,
     int render_view_host_routing_id,
@@ -129,11 +129,9 @@ void PluginInstaller::RemoveWeakObserver(
   weak_observers_.RemoveObserver(observer);
 }
 
-void PluginInstaller::StartInstalling(bool url_for_display,
-                                      const GURL& plugin_url,
+void PluginInstaller::StartInstalling(GURL plugin_url,
                                       TabContents* tab_contents) {
   DCHECK_EQ(INSTALLER_STATE_IDLE, state_);
-  DCHECK(url_for_display);
   state_ = INSTALLER_STATE_DOWNLOADING;
   FOR_EACH_OBSERVER(PluginInstallerObserver, observers_, DownloadStarted());
   content::WebContents* web_contents = tab_contents->web_contents();
@@ -174,11 +172,9 @@ void PluginInstaller::DownloadStarted(
   download_item->AddObserver(this);
 }
 
-void PluginInstaller::OpenDownloadURL(bool url_for_display,
-                                      const GURL& plugin_url,
+void PluginInstaller::OpenDownloadURL(GURL plugin_url,

[ibraaaa, 2012/10/05 11:14:07]

Here a copy is made directly in |OpenURLParams()| but I passed it by value for
consistency.

[Bernhard Bauer, 2012/10/05 11:16:30]

Consistency with what? Note that we usually pass objects by const-reference.

[ibraaaa, 2012/10/05 11:23:36]

Well I thought this way. If a refactor is done to this method that involves a
change similar to the one that caused the bug above then this may lead to
another bug. You can always correct me.

On 2012/10/05 11:16:30, Bernhard Bauer wrote:

[Bernhard Bauer, 2012/10/05 12:01:57]

Wait, do we know that this fixes the crash? It seems like we're passing a
reference to something that has gone away, so we crash when trying to
dereference it for the first time (i.e. copying it into the base::Bind closure).
Passing it by value would only make it crash sooner in that case.

                                       content::WebContents* web_contents) {
   DCHECK_EQ(INSTALLER_STATE_IDLE, state_);
-  DCHECK(url_for_display);
   web_contents->OpenURL(content::OpenURLParams(
       plugin_url,
       content::Referrer(web_contents->GetURL(),