Only load inline text boxes for the node that has accessibility focus.

This is a significant optimization for Android accessibility; avoiding
loading inline text boxes on the whole tree makes page loads 20% faster,
but we can still get all of the benefit by tracking which node has
accessibility focus and loading inline text boxes for only that subtree,
asynchronously.

Depends on: https://codereview.chromium.org/700373007

BUG=378810

Review URL: https://codereview.chromium.org/743413002

Cr-Commit-Position: refs/heads/master@{#305737}

1 files changed, 9 insertions, 0 deletions

diff --git a/content/browser/accessibility/browser_accessibility_manager_android.cc b/content/browser/accessibility/browser_accessibility_manager_android.cc
index 8bc13c8..fd4e0ff 100644
--- a/content/browser/accessibility/browser_accessibility_manager_android.cc
+++ b/content/browser/accessibility/browser_accessibility_manager_android.cc
@@ -122,6 +122,9 @@ void BrowserAccessibilityManagerAndroid::NotifyAccessibilityEvent(
   if (event_type == ui::AX_EVENT_HIDE)
     return;
 
+  if (event_type == ui::AX_EVENT_TREE_CHANGED)
+    return;
+
   if (event_type == ui::AX_EVENT_HOVER) {
     HandleHoverEvent(node);
     return;
@@ -715,6 +718,12 @@ bool BrowserAccessibilityManagerAndroid::PreviousAtGranularity(
   return true;
 }
 
+void BrowserAccessibilityManagerAndroid::SetAccessibilityFocus(
+    JNIEnv* env, jobject obj, jint id) {
+  if (delegate_)
+    delegate_->AccessibilitySetAccessibilityFocus(id);
+}
+
 void BrowserAccessibilityManagerAndroid::OnRootChanged(ui::AXNode* new_root) {
   JNIEnv* env = AttachCurrentThread();
   ScopedJavaLocalRef<jobject> obj = java_ref_.get(env);