Support multi-button press for synthetic mouse events

content/common/input/synthetic_pointer_action_params.h

Index: content/common/input/synthetic_pointer_action_params.h
diff --git a/content/common/input/synthetic_pointer_action_params.h b/content/common/input/synthetic_pointer_action_params.h
index 6b4e74c358f30a47118e3e086a83f25e61d3261b..173fa4069789702f687dc005cb26a75afb29de67 100644
--- a/content/common/input/synthetic_pointer_action_params.h
+++ b/content/common/input/synthetic_pointer_action_params.h
@@ -51,6 +51,14 @@ struct CONTENT_EXPORT SyntheticPointerActionParams {
     position_ = position;
   }
 
+  void set_button(int button) {
+    DCHECK(pointer_action_type_ == PointerActionType::PRESS ||
+           pointer_action_type_ == PointerActionType::RELEASE);
+    DCHECK_GE(button, 0);
+    DCHECK_LE(button, 2);
+    button_ = button;
+  }
+
   PointerActionType pointer_action_type() const { return pointer_action_type_; }
 
   int index() const {
@@ -65,6 +73,14 @@ struct CONTENT_EXPORT SyntheticPointerActionParams {
     return position_;
   }
 
+  int button() const {
+    DCHECK(pointer_action_type_ == PointerActionType::PRESS ||
+           pointer_action_type_ == PointerActionType::RELEASE);
+    DCHECK_GE(button_, 0);
+    DCHECK_LE(button_, 2);
+    return button_;
+  }
+
  private:
   friend struct IPC::ParamTraits<content::SyntheticPointerActionParams>;
   friend struct ipc_fuzzer::FuzzTraits<content::SyntheticPointerActionParams>;
@@ -75,6 +91,7 @@ struct CONTENT_EXPORT SyntheticPointerActionParams {
   // The index of the pointer in the pointer action sequence passed from the
   // user API.
   int index_;
+  int button_;
 };
 
 }  // namespace content