A few minor changes to the chrome.downloads extension API

chrome/browser/download/download_danger_prompt.cc

Index: chrome/browser/download/download_danger_prompt.cc
diff --git a/chrome/browser/download/download_danger_prompt.cc b/chrome/browser/download/download_danger_prompt.cc
index bdd75cc4d58c2eb7c6cc8cabcdf19b80154d5bef..924abe5caa059c634b1fb9abdbe07e411d8d9da8 100644
--- a/chrome/browser/download/download_danger_prompt.cc
+++ b/chrome/browser/download/download_danger_prompt.cc
@@ -8,6 +8,7 @@
 #include "chrome/browser/download/chrome_download_manager_delegate.h"
 #include "chrome/browser/ui/tab_modal_confirm_dialog.h"
 #include "chrome/browser/ui/tab_modal_confirm_dialog_delegate.h"
+#include "chrome/common/chrome_notification_types.h"
 #include "content/public/browser/download_danger_type.h"
 #include "content/public/browser/download_item.h"
 #include "grit/generated_resources.h"
@@ -25,7 +26,8 @@ class DownloadDangerPromptImpl
                            content::WebContents* web_contents,
                            bool show_context,
                            const base::Closure& accepted,
-                           const base::Closure& canceled);
+                           const base::Closure& canceled,
+                           const base::Closure& destroyed);
   virtual ~DownloadDangerPromptImpl();
 
   // DownloadDangerPrompt
@@ -43,6 +45,12 @@ class DownloadDangerPromptImpl
   virtual void OnAccepted() OVERRIDE;
   virtual void OnCanceled() OVERRIDE;
 
+  // content::NotificationObserver implementation.
+  virtual void Observe(
+      int type,
+      const content::NotificationSource& source,
+      const content::NotificationDetails& details) OVERRIDE;
+
   // Runs |callback|. PrepareToClose() is called beforehand. Doing so prevents
   // this object from responding to state changes in |download_| that might
   // result from invoking the callback. |callback| must refer to either
@@ -57,6 +65,7 @@ class DownloadDangerPromptImpl
   bool show_context_;
   base::Closure accepted_;
   base::Closure canceled_;
+  base::Closure destroyed_;
 
   DISALLOW_COPY_AND_ASSIGN(DownloadDangerPromptImpl);
 };
@@ -66,12 +75,14 @@ DownloadDangerPromptImpl::DownloadDangerPromptImpl(
     content::WebContents* web_contents,
     bool show_context,
     const base::Closure& accepted,
-    const base::Closure& canceled)
+    const base::Closure& canceled,
+    const base::Closure& destroyed)
     : TabModalConfirmDialogDelegate(web_contents),
       download_(download),
       show_context_(show_context),
       accepted_(accepted),
-      canceled_(canceled) {
+      canceled_(canceled),
+      destroyed_(destroyed) {
   DCHECK(!accepted_.is_null());
   // canceled_ is allowed to be null.
   DCHECK(download_);
@@ -81,7 +92,11 @@ DownloadDangerPromptImpl::DownloadDangerPromptImpl(
 DownloadDangerPromptImpl::~DownloadDangerPromptImpl() {
   // |this| might be deleted without invoking any callbacks. E.g. pressing Esc
   // on GTK or if the user navigates away from the page showing the prompt.
+  base::Closure destroyed = destroyed_;
+  destroyed_.Reset();
   PrepareToClose();
+  if (!destroyed.is_null())
+    destroyed.Run();
 }
 
 void DownloadDangerPromptImpl::InvokeActionForTesting(Action action) {
@@ -96,8 +111,11 @@ void DownloadDangerPromptImpl::OnDownloadUpdated(
   // If the download is nolonger dangerous (accepted externally) or the download
   // is in a terminal state, then the download danger prompt is no longer
   // necessary.
-  if (!download->IsDangerous() || download->IsDone())
+  if (!download->IsDangerous() || download->IsDone()) {
+    accepted_.Reset();
+    canceled_.Reset();
     Cancel();
+  }
 }
 
 void DownloadDangerPromptImpl::OnDownloadOpened(
@@ -146,6 +164,21 @@ void DownloadDangerPromptImpl::OnCanceled() {
   RunCallback(canceled_);
 }
 
+void DownloadDangerPromptImpl::Observe(
+    int type,
+    const content::NotificationSource& source,
+    const content::NotificationDetails& details) {
+  // Same logic as TabModalConfirmDialogDelegate::Observe, but don't run
+  // canceled_. Just run destroyed_.
+  if (type == content::NOTIFICATION_LOAD_START ||
+      type == chrome::NOTIFICATION_TAB_CLOSING) {
+    PrepareToClose();
+    Cancel();
+  } else {
+    NOTREACHED();
+  }
+}
+
 void DownloadDangerPromptImpl::RunCallback(const base::Closure& callback) {
   // Invoking the callback can cause the download item state to change or cause
   // the constrained window to close, and |callback| refers to a member
@@ -173,9 +206,10 @@ DownloadDangerPrompt* DownloadDangerPrompt::Create(
     content::WebContents* web_contents,
     bool show_context,
     const base::Closure& accepted,
-    const base::Closure& canceled) {
+    const base::Closure& canceled,
+    const base::Closure& destroyed) {
   DownloadDangerPromptImpl* prompt = new DownloadDangerPromptImpl(
-      item, web_contents, show_context, accepted, canceled);
+      item, web_contents, show_context, accepted, canceled, destroyed);
   // |prompt| will be deleted when the dialog is done.
   TabModalConfirmDialog::Create(prompt, web_contents);
   return prompt;