Expand Chrome OS ARC support to create one tree source per package

components/arc/common/accessibility_helper.mojom

Index: components/arc/common/accessibility_helper.mojom
diff --git a/components/arc/common/accessibility_helper.mojom b/components/arc/common/accessibility_helper.mojom
index d80b7355993d7e2e21eef62df5b15d09fd3ff340..c7703fe2426fe2bc835515dea32029c5218e37a9 100644
--- a/components/arc/common/accessibility_helper.mojom
+++ b/components/arc/common/accessibility_helper.mojom
@@ -156,7 +156,10 @@ enum AccessibilityFilterType {
   FOCUS,
 
   // Send a complete tree from the event source's root for every event.
-  ALL
+  ALL,
+
+  // Send complete subtrees for root nodes with whitelisted package names.
+  WHITELISTED_PACKAGE_NAME
 };
 
 // AccessibilityEventData is a struct to contain info of
@@ -178,7 +181,7 @@ interface AccessibilityHelperHost {
   OnAccessibilityEvent@1(AccessibilityEventData eventData);
 };
 
-// Next method ID: 3
+// Next method ID: 4
 interface AccessibilityHelperInstance {
   Init@0(AccessibilityHelperHost host);
 
@@ -187,4 +190,7 @@ interface AccessibilityHelperInstance {
 
   // Set a filter on the event types received.
   SetFilter@2(AccessibilityFilterType filterType);
+
+  // Sets native Chrome accessibility support on or off for the current package.
+  SetCurrentPackageNativeAccessibility@3(bool enabled);

[yawano, 2017/04/27 10:01:27]

Wouldn't this cause race condition? i.e. current package might not match between
Chrome and Android. How about to change this as
setChromeAccessibilitySupportEnabled(bool enabled, string package_name)?

[David Tseng, 2017/04/28 00:27:44]

Yes, you're right. I was adding this to avoid another review, but since this
ins't being called at all, I'll defer this to another cl, where it would be
exercised by ChromeVox.

It's pretty clear I should add a test suite for everything in this cl as well.

 };