Switch AccessibilityMode to be a bitmap

content/browser/accessibility/browser_accessibility_state_impl.cc

Index: content/browser/accessibility/browser_accessibility_state_impl.cc
diff --git a/content/browser/accessibility/browser_accessibility_state_impl.cc b/content/browser/accessibility/browser_accessibility_state_impl.cc
index 3dee7d62b33d46a055500af0e3ee6dd9d87508b0..4cd86f830b44a9c79d4e9d4eb2fc7c8ac784cb2c 100644
--- a/content/browser/accessibility/browser_accessibility_state_impl.cc
+++ b/content/browser/accessibility/browser_accessibility_state_impl.cc
@@ -7,6 +7,7 @@
 #include "base/command_line.h"
 #include "base/metrics/histogram.h"
 #include "base/timer/timer.h"
+#include "content/browser/accessibility/accessibility_mode_helper.h"
 #include "content/browser/renderer_host/render_widget_host_impl.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/render_process_host.h"
@@ -80,20 +81,21 @@ void BrowserAccessibilityStateImpl::OnScreenReaderDetected() {
           switches::kDisableRendererAccessibility)) {
     return;
   }
-  SetAccessibilityMode(AccessibilityModeComplete);
+  AddAccessibilityMode(AccessibilityModeComplete);
 }
 
 void BrowserAccessibilityStateImpl::EnableAccessibility() {
   // We may want to do something different with this later.
-  SetAccessibilityMode(AccessibilityModeComplete);
+  AddAccessibilityMode(AccessibilityModeComplete);
 }
 
 void BrowserAccessibilityStateImpl::DisableAccessibility() {
-  SetAccessibilityMode(AccessibilityModeOff);
+  RemoveAccessibilityMode(AccessibilityModeAll);
 }
 
 bool BrowserAccessibilityStateImpl::IsAccessibleBrowser() {
-  return (accessibility_mode_ == AccessibilityModeComplete);
+  return ((accessibility_mode_ & AccessibilityModeComplete) ==
+          AccessibilityModeComplete);
 }
 
 void BrowserAccessibilityStateImpl::AddHistogramCallback(
@@ -124,12 +126,31 @@ void BrowserAccessibilityStateImpl::UpdatePlatformSpecificHistograms() {
 }
 #endif
 
-void BrowserAccessibilityStateImpl::SetAccessibilityMode(
+void BrowserAccessibilityStateImpl::AddAccessibilityMode(
     AccessibilityMode mode) {
-  if (accessibility_mode_ == mode)
+  if ((accessibility_mode_ & mode) == mode)
     return;
-  accessibility_mode_ = mode;
 
+  accessibility_mode_ =
+      content::AddAccessibilityMode(accessibility_mode_, mode);

[David Tseng, 2014/02/04 20:25:51]

By setting text only, then complete, I would end up adding both text only and
complete, which is a functional change from the current code. (see my comments
about enforcement on add).

[aboxhall, 2014/02/05 16:02:47]

Complete + text only should be considered to be text only, IMO.

+
+  AddOrRemoveFromRenderWidgets(mode, true);
+}
+
+void BrowserAccessibilityStateImpl::RemoveAccessibilityMode(
+    AccessibilityMode mode) {
+  if ((accessibility_mode_ ^ mode) == mode)
+    return;
+
+  accessibility_mode_ =
+      content::RemoveAccessibilityMode(accessibility_mode_, mode);
+
+  AddOrRemoveFromRenderWidgets(mode, false);
+}
+
+void BrowserAccessibilityStateImpl::AddOrRemoveFromRenderWidgets(
+    AccessibilityMode mode,
+    bool add) {
   // Iterate over all RenderWidgetHosts, even swapped out ones in case
   // they become active again.
   scoped_ptr<RenderWidgetHostIterator> widgets(
@@ -141,7 +162,11 @@ void BrowserAccessibilityStateImpl::SetAccessibilityMode(
     if (!widget->IsRenderView())
       continue;
 
-    RenderWidgetHostImpl::From(widget)->SetAccessibilityMode(mode);
+    RenderWidgetHostImpl* rwhi = RenderWidgetHostImpl::From(widget);
+    if (add)
+      rwhi->AddAccessibilityMode(mode);
+    else
+      rwhi->RemoveAccessibilityMode(mode);
   }
 }