Handles aria-dropeffect after getting its value from blink.

content/browser/accessibility/browser_accessibility_cocoa.mm

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <execinfo.h>
 
 #import "content/browser/accessibility/browser_accessibility_cocoa.h"
 
 #include <map>
 
@@ skipping 91 matching lines @@
     { NSAccessibilityVisibleCellsAttribute, @"visibleCells" },
     { NSAccessibilityVisibleChildrenAttribute, @"visibleChildren" },
     { NSAccessibilityVisibleColumnsAttribute, @"visibleColumns" },
     { NSAccessibilityVisibleRowsAttribute, @"visibleRows" },
     { NSAccessibilityWindowAttribute, @"window" },
     { @"AXAccessKey", @"accessKey" },
     { @"AXARIAAtomic", @"ariaAtomic" },
     { @"AXARIABusy", @"ariaBusy" },
     { @"AXARIALive", @"ariaLive" },
     { @"AXARIARelevant", @"ariaRelevant" },
+    { @"AXDropEffects", @"dropeffect" },
     { @"AXGrabbed", @"grabbed" },
     { @"AXInvalid", @"invalid" },
     { @"AXLoaded", @"loaded" },
     { @"AXLoadingProgress", @"loadingProgress" },
     { @"AXPlaceholder", @"placeholder" },
     { @"AXRequired", @"required" },
     { @"AXVisited", @"visited" },
   };
 
   NSMutableDictionary* dict = [[NSMutableDictionary alloc] init];
@@ skipping 198 matching lines @@
   } else {
     return nil;
   }
 }
 
 - (id)disclosedRows {
   // The rows that are considered inside this row.
   return nil;
 }
 
+- (NSString*)dropeffect {
+  return NSStringForStringAttribute(
+      browserAccessibility_, ui::AX_ATTR_DROPEFFECT);
+}
+
 - (NSNumber*)enabled {
   return [NSNumber numberWithBool:
       GetState(browserAccessibility_, ui::AX_STATE_ENABLED)];
 }
 
 - (NSNumber*)expanded {
   return [NSNumber numberWithBool:
       GetState(browserAccessibility_, ui::AX_STATE_EXPANDED)];
 }
 
@@ skipping 1045 matching lines @@
     [ret addObjectsFromArray:[NSArray arrayWithObjects:
         @"AXARIAAtomic",
         nil]];
   }
   if (browserAccessibility_->HasBoolAttribute(
           ui::AX_ATTR_LIVE_BUSY)) {
     [ret addObjectsFromArray:[NSArray arrayWithObjects:
         @"AXARIABusy",
         nil]];
   }
+
+  if (browserAccessibility_->HasStringAttribute(
+          ui::AX_ATTR_DROPEFFECT)) {
+    [ret addObjectsFromArray:[NSArray arrayWithObjects:
+        @"AXDropEffects",
+        nil]];
+  }
+
   // Add aria-grabbed attribute only if it has true.
   if (browserAccessibility_->HasBoolAttribute(ui::AX_ATTR_GRABBED)) {
     [ret addObjectsFromArray:[NSArray arrayWithObjects:
         @"AXGrabbed",
         nil]];
   }
 
   // Add expanded attribute only if it has expanded or collapsed state.
   if (GetState(browserAccessibility_, ui::AX_STATE_EXPANDED) ||
         GetState(browserAccessibility_, ui::AX_STATE_COLLAPSED)) {
@@ skipping 172 matching lines @@
   if (!browserAccessibility_)
     return [super hash];
   return browserAccessibility_->GetId();
 }
 
 - (BOOL)accessibilityShouldUseUniqueId {
   return YES;
 }
 
 @end