Make tests wait until automation is done to prevent leaks

third_party/WebKit/LayoutTests/imported/wpt_automation/pointerevents/pointerevent_capture_mouse-manual-automation.js

Index: third_party/WebKit/LayoutTests/imported/wpt_automation/pointerevents/pointerevent_capture_mouse-manual-automation.js
diff --git a/third_party/WebKit/LayoutTests/imported/wpt_automation/pointerevents/pointerevent_capture_mouse-manual-automation.js b/third_party/WebKit/LayoutTests/imported/wpt_automation/pointerevents/pointerevent_capture_mouse-manual-automation.js
index 2c681ca2fe28ffaca38e6022b4192239dd13d17d..2cccec5d14766d417b0d5ee135a75ccebdab63f8 100644
--- a/third_party/WebKit/LayoutTests/imported/wpt_automation/pointerevents/pointerevent_capture_mouse-manual-automation.js
+++ b/third_party/WebKit/LayoutTests/imported/wpt_automation/pointerevents/pointerevent_capture_mouse-manual-automation.js
@@ -1,10 +1,12 @@
 importAutomationScript('/pointerevents/pointerevent_common_input.js');
 
 function inject_input() {
-  mouseMoveIntoTarget('target0');
-  mouseMoveIntoTarget('target1');
-  mouseDragInTargets(['btnCapture', 'target1', 'target0']);
-
-  // To handle delayed capturing
-  mouseMoveIntoTarget('target0');
+  return mouseMoveIntoTarget('target0').then(function() {
+    return mouseMoveIntoTarget('target1');
+  }).then(function() {
+    return mouseDragInTargets(['btnCapture', 'target1', 'target0']);
+  }).then(function() {
+    // To handle delayed capturing.
+    return mouseMoveIntoTarget('target0');
+  });
 }