Fix is_browser_shortcut; add a test.

chrome/browser/ui/cocoa/browser_window_cocoa.mm

Index: chrome/browser/ui/cocoa/browser_window_cocoa.mm
diff --git a/chrome/browser/ui/cocoa/browser_window_cocoa.mm b/chrome/browser/ui/cocoa/browser_window_cocoa.mm
index 3ddde63bcce6dc21dcdc039133f8898c510d971f..d9cc8b301968ee882bea91803d0b6be6bd6f8913 100644
--- a/chrome/browser/ui/cocoa/browser_window_cocoa.mm
+++ b/chrome/browser/ui/cocoa/browser_window_cocoa.mm
@@ -6,6 +6,7 @@
 
 #include "base/bind.h"
 #include "base/command_line.h"
+#include "base/debug/stack_trace.h"
 #include "base/logging.h"
 #import "base/mac/sdk_forward_declarations.h"
 #include "base/message_loop/message_loop.h"
@@ -582,32 +583,41 @@ void BrowserWindowCocoa::ShowAppMenu() {
 content::KeyboardEventProcessingResult
 BrowserWindowCocoa::PreHandleKeyboardEvent(
     const NativeWebKeyboardEvent& event) {
+  base::debug::StackTrace s;
+  LOG(ERROR) << "BrowserWindowCocoa::PreHandleKeyboardEvent\n" << s.ToString();
   // Handle ESC to dismiss permission bubbles, but still forward it
   // to the window afterwards.
   if (event.windows_key_code == ui::VKEY_ESCAPE)
     [controller_ dismissPermissionBubble];
 
-  if (![BrowserWindowUtils shouldHandleKeyboardEvent:event])
+  if (![BrowserWindowUtils shouldHandleKeyboardEvent:event]) {
+    LOG(ERROR) << " > early exit; shouldn't handle event";
     return content::KeyboardEventProcessingResult::NOT_HANDLED;
+  }
 
   if (event.GetType() == blink::WebInputEvent::kRawKeyDown &&
       [controller_
           handledByExtensionCommand:event.os_event
-                           priority:ui::AcceleratorManager::kHighPriority])
+                           priority:ui::AcceleratorManager::kHighPriority]) {
+    LOG(ERROR) << " > handled by extension command";
     return content::KeyboardEventProcessingResult::HANDLED;
+  }
 
   int id = [BrowserWindowUtils getCommandId:event];
-  if (id == -1)
+  if (id == -1) {
+    LOG(ERROR) << " > not handled; no command id";
     return content::KeyboardEventProcessingResult::NOT_HANDLED;
+  }
 
   if (browser_->command_controller()->IsReservedCommandOrKey(id, event)) {
     using Result = content::KeyboardEventProcessingResult;
-    return [BrowserWindowUtils handleKeyboardEvent:event.os_event
-                                          inWindow:window()]
-               ? Result::HANDLED
-               : Result::NOT_HANDLED;
+    bool result = [BrowserWindowUtils handleKeyboardEvent:event.os_event
+                                                 inWindow:window()];
+    LOG(ERROR) << " > handleKeyboardEvent: returned " << result;
+    return result ? Result::HANDLED : Result::NOT_HANDLED;
   }
 
+  LOG(ERROR) << " > returning default";
   return content::KeyboardEventProcessingResult::NOT_HANDLED_IS_SHORTCUT;
 }