Add custom action support

chrome/common/extensions/api/automation.idl

Index: chrome/common/extensions/api/automation.idl
diff --git a/chrome/common/extensions/api/automation.idl b/chrome/common/extensions/api/automation.idl
index 4c6e957966b3bf13197774471f196679cd891c06..61f6d139468bebf3d7d5577edad0c24611a4776f 100644
--- a/chrome/common/extensions/api/automation.idl
+++ b/chrome/common/extensions/api/automation.idl
@@ -367,6 +367,11 @@
   // A listener for changes on the <code>AutomationNode</code> tree.
   callback TreeChangeObserver = void(TreeChange treeChange);
 
+  dictionary CustomAction {
+    long id;
+    DOMString description;
+  };
+
   // A single node in an Automation tree.
   [nocompile, noinline_doc] dictionary AutomationNode {
     // The root node of the tree containing this AutomationNode.
@@ -447,6 +452,9 @@
     // The target of an in-page link.
     AutomationNode? inPageLinkTarget;
 
+    // An array of custom actions.
+    CustomAction[]? customActions;
+
     //
     // Link attributes.
     //
@@ -708,6 +716,9 @@
     // Scrolls this node to make it visible.
     static void makeVisible();
 
+    // Performs custom action.
+    static void performCustomAction(long customActionId);

[dmazzoni, 2017/06/06 03:06:00]

Would it be cleaner if this took a CustomAction as its argument, then
we extract the action id inside the internal bindings?

[yawano, 2017/06/08 09:25:29]

Done. Yes, also it should be more extensible.

+
     // Sets selection within a text field.
     static void setSelection(long startIndex, long endIndex);