Corner Passthrough for Accessibility

chrome/browser/ui/ash/chrome_shell_delegate_chromeos.cc

Index: chrome/browser/ui/ash/chrome_shell_delegate_chromeos.cc
diff --git a/chrome/browser/ui/ash/chrome_shell_delegate_chromeos.cc b/chrome/browser/ui/ash/chrome_shell_delegate_chromeos.cc
index 674459629c643bc302ce74be58929b8332a68fb4..77abb42a4067f5f39a9e729be8c2a3b4e007b2d4 100644
--- a/chrome/browser/ui/ash/chrome_shell_delegate_chromeos.cc
+++ b/chrome/browser/ui/ash/chrome_shell_delegate_chromeos.cc
@@ -38,6 +38,7 @@
 #include "content/public/browser/notification_service.h"
 #include "content/public/browser/user_metrics.h"
 #include "grit/generated_resources.h"
+#include "media/audio/sounds/sounds_manager.h"
 #include "ui/aura/window.h"
 #include "ui/base/l10n/l10n_util.h"
 
@@ -199,6 +200,11 @@ class AccessibilityDelegateImpl : public ash::AccessibilityDelegate {
     return ash::A11Y_ALERT_NONE;
   }
 
+  virtual void PlayEarcon(media::SoundsManager::SoundKey sound_key) OVERRIDE {
+    DCHECK(chromeos::AccessibilityManager::Get());

[James Cook, 2014/07/29 04:27:24]

We don't generally DCHECK something just before dereferencing it. If it's null,
the next line will just crash and it should be obvious why.

[dmazzoni, 2014/07/29 05:47:50]

I see that pattern a fair amount. Must be different conventions in different
parts of the code.

[James Cook, 2014/07/29 15:45:51]

Yeah. I use it as a way to establish preconditions for input to a function,
especially if that function is long:

void Foo(A* a, B* b) {
  DCHECK(a);  // precondition
  // No DCHECK(b) so it's probably OK to be NULL
  ...lots of code...
  a->DoSomething();
}

But I generally don't for things like:

void Foo(A* a, B* b) {
  a->DoSomething();  // Should be immediately obvious it can't be null
}

or

void Foo() {
  SomeAnnoyingSingleton::Get()->DoSomething();
}

That said, the rest of this file DCHECK's it, so in the interest of consistency,
keep the DCHECK.

[lisayin, 2014/07/30 15:32:51]

Acknowledged.

+    return chromeos::AccessibilityManager::Get()->PlayEarcon(sound_key);
+  }
+
   virtual base::TimeDelta PlayShutdownSound() const OVERRIDE {
     return chromeos::AccessibilityManager::Get()->PlayShutdownSound();
   }