Add support for faster, more limited accessibility modes.

content/browser/renderer_host/legacy_render_widget_host_win.cc

Index: content/browser/renderer_host/legacy_render_widget_host_win.cc
diff --git a/content/browser/renderer_host/legacy_render_widget_host_win.cc b/content/browser/renderer_host/legacy_render_widget_host_win.cc
index 663ea76667b6be6ba0413745f3f4e3204a18beaf..8d3f11cba47bc494887ce2c022954c729fd6ed05 100644
--- a/content/browser/renderer_host/legacy_render_widget_host_win.cc
+++ b/content/browser/renderer_host/legacy_render_widget_host_win.cc
@@ -10,10 +10,10 @@
 #include "base/win/win_util.h"
 #include "base/win/windows_version.h"
 #include "content/browser/accessibility/browser_accessibility_manager_win.h"
+#include "content/browser/accessibility/browser_accessibility_state_impl.h"
 #include "content/browser/accessibility/browser_accessibility_win.h"
 #include "content/browser/renderer_host/render_widget_host_impl.h"
 #include "content/browser/renderer_host/render_widget_host_view_aura.h"
-#include "content/public/browser/browser_accessibility_state.h"
 #include "content/public/common/content_switches.h"
 #include "ui/base/view_prop.h"
 #include "ui/base/win/internal_constants.h"
@@ -119,7 +119,9 @@ bool LegacyRenderWidgetHostHWND::Init() {
       reinterpret_cast<void **>(window_accessible_.Receive()));
   DCHECK(SUCCEEDED(hr));
 
-  if (!BrowserAccessibilityState::GetInstance()->IsAccessibleBrowser()) {
+  AccessibilityMode mode =
+      BrowserAccessibilityStateImpl::GetInstance()->accessibility_mode();
+  if (!(mode & ACCESSIBILITY_MODE_FLAG_NATIVE_APIS)) {
     // Attempt to detect screen readers or other clients who want full
     // accessibility support, by seeing if they respond to this event.
     NotifyWinEvent(EVENT_SYSTEM_ALERT, hwnd(), kIdScreenReaderHoneyPot,
@@ -161,8 +163,11 @@ LRESULT LegacyRenderWidgetHostHWND::OnGetObject(UINT message,
 
   if (kIdScreenReaderHoneyPot == obj_id) {
     // When an MSAA client has responded to our fake event on this id,
-    // enable screen reader support.
-    BrowserAccessibilityState::GetInstance()->OnScreenReaderDetected();
+    // enable basic accessibility support. (Full screen reader support is
+    // detected later when specific more advanced APIs are accessed.)
+    BrowserAccessibilityStateImpl::GetInstance()->AddAccessibilityModeFlags(
+        ACCESSIBILITY_MODE_FLAG_NATIVE_APIS |
+        ACCESSIBILITY_MODE_FLAG_WEB_CONTENTS);
     return static_cast<LRESULT>(0L);
   }