Fix build break from a bad rebase.

Broken in 93d013c2dc798e50cd60f3c85bf859fc98a264f8
Bad rebase of services/window_manager/window_manager_app.cc

BUG=NONE
TBR=sky@chromium.org

Review URL: https://codereview.chromium.org/831663006
diff --git a/services/window_manager/window_manager_app.cc b/services/window_manager/window_manager_app.cc
index c71c37f..56dbbc4 100644
--- a/services/window_manager/window_manager_app.cc
+++ b/services/window_manager/window_manager_app.cc
@@ -56,8 +56,7 @@
       native_viewport_event_dispatcher_factory_(this),
       wrapped_view_manager_delegate_(view_manager_delegate),
       window_manager_delegate_(window_manager_delegate),
-      root_(nullptr),
-      gesture_provider_(this) {
+      root_(nullptr) {
 }
 
 WindowManagerApp::~WindowManagerApp() {