Fixes the crash for "learn more" link of the dialog for v2 apps.

chrome/browser/chromeos/attestation/platform_verification_dialog.cc

Index: chrome/browser/chromeos/attestation/platform_verification_dialog.cc
diff --git a/chrome/browser/chromeos/attestation/platform_verification_dialog.cc b/chrome/browser/chromeos/attestation/platform_verification_dialog.cc
index 097b0507b7b473341100734c3f7847178901bcf9..f2255656ecbe0b502796acf6af9144e5da0cf1ab 100644
--- a/chrome/browser/chromeos/attestation/platform_verification_dialog.cc
+++ b/chrome/browser/chromeos/attestation/platform_verification_dialog.cc
@@ -6,6 +6,7 @@
 
 #include "base/strings/utf_string_conversions.h"
 #include "chrome/browser/ui/browser_finder.h"

[bartfab (slow), 2014/04/16 12:22:42]

Nit: No longer used.

[Jun Mukai, 2014/04/16 18:00:59]

browser_finder is still used in line 132 below

+#include "chrome/browser/ui/browser_navigator.h"
 #include "chrome/browser/ui/browser_window.h"
 #include "chrome/browser/ui/singleton_tabs.h"
 #include "chrome/common/url_constants.h"
@@ -46,7 +47,7 @@ void PlatformVerificationDialog::ShowDialog(
   std::string origin = extension ? extension->name() : url.GetOrigin().spec();
 
   PlatformVerificationDialog* dialog = new PlatformVerificationDialog(
-      chrome::FindBrowserWithWebContents(web_contents),
+      web_contents,
       base::UTF8ToUTF16(origin),
       callback);
 
@@ -66,10 +67,10 @@ PlatformVerificationDialog::~PlatformVerificationDialog() {
 }
 
 PlatformVerificationDialog::PlatformVerificationDialog(
-    Browser* browser,
+    content::WebContents* web_contents,
     const base::string16& domain,
     const PlatformVerificationFlow::Delegate::ConsentCallback& callback)
-    : browser_(browser),
+    : web_contents_(web_contents),
       domain_(domain),
       callback_(callback) {
   SetLayoutManager(new views::FillLayout());
@@ -128,8 +129,21 @@ gfx::Size PlatformVerificationDialog::GetPreferredSize() {
 
 void PlatformVerificationDialog::StyledLabelLinkClicked(const gfx::Range& range,
                                                         int event_flags) {
-  chrome::ShowSingletonTab(browser_, GURL(
-      chrome::kEnhancedPlaybackNotificationLearnMoreURL));
+  Browser* browser = chrome::FindBrowserWithWebContents(web_contents_);
+  GURL learn_more_url(chrome::kEnhancedPlaybackNotificationLearnMoreURL);

[bartfab (slow), 2014/04/16 12:22:42]

Nit: const.

[Jun Mukai, 2014/04/16 18:00:59]

Done.

+
+  // |web_contents_| might not have a browser in case of v2 apps, in that case

[bartfab (slow), 2014/04/16 12:22:42]

Nit: s/, in that case/. In that case,/

[Jun Mukai, 2014/04/16 18:00:59]

Done.

+  // open a new tab in a usual way.

[bartfab (slow), 2014/04/16 12:22:42]

1: Nit: s/ a / the /
2: How do you open a new tab when there is no browser? Is it not that you
actually open a whole new browser, which then contains one tab?

[Jun Mukai, 2014/04/16 18:00:59]

1: done.

2: as far as I see browser_navigator.cc, it will open a new browser window with
a new tab, or use a new tab in an existing browser window if exists.  Note that
this is not the case of 'no browser window'.  This is 'web_contents is not in a
browser window'. There might be other browser windows.
Do you feel to describe whole things?

[bartfab (slow), 2014/04/16 18:38:59]

Thanks for clarifying. I am so used to Chrome OS single-app kiosk mode that
whenever I hear app v2, I think "app that owns the entire screen - no other
browser windows." That confused me here. I think there is no need to add any
comments - all confusion has been addressed.

[Jun Mukai, 2014/04/16 21:23:41]

The report is saying a normal v2 app in a normal chromebook, but certainly there
are no browser windows in the Kiosk mode.
I'll double-check with the PM but I think this dialog is not used in Kiosk mode.

[Jun Mukai, 2014/04/17 01:33:53]

we do not have any plan to provide this in Kiosk apps so I'll put this into CQ.

+  if (!browser) {
+    Profile* profile = Profile::FromBrowserContext(

[bartfab (slow), 2014/04/16 12:22:42]

Nit: #include "chrome/browser/profiles/profile.h"

[Jun Mukai, 2014/04/16 18:00:59]

Done.

+        web_contents_->GetBrowserContext());
+    chrome::NavigateParams params(
+        profile, learn_more_url, content::PAGE_TRANSITION_LINK);

[bartfab (slow), 2014/04/16 12:22:42]

Nit: #include "content/public/common/page_transition_types.h"

[Jun Mukai, 2014/04/16 18:00:59]

Done.

[Jun Mukai, 2014/04/16 18:00:59]

Done.

+    chrome::Navigate(&params);
+  } else {
+    chrome::ShowSingletonTab(browser, GURL(

[bartfab (slow), 2014/04/16 12:22:42]

Nit: Use the |learn_more_url| constructed above instead of reconstructing it
here.

[Jun Mukai, 2014/04/16 18:00:59]

Done.

+        chrome::kEnhancedPlaybackNotificationLearnMoreURL));
+  }
 }
 
 }  // namespace attestation