Add support for touch-action: pinch-zoom.

third_party/WebKit/LayoutTests/imported/wpt_automation/pointerevents/pointerevent_common_input.js

 // This file contains the commonly used functions in pointerevent tests.
 
 const scrollOffset = 30;
 const boundaryOffset = 5;
 const touchSourceType = 1;
 
 function delayPromise(delay) {
   return new Promise(function(resolve, reject) {
     window.setTimeout(resolve, delay);
   });
@@ skipping 120 matching lines @@
       var target = document.querySelector(targetSelector);
       var targetRect = target.getBoundingClientRect();
       chrome.gpuBenchmarking.smoothScrollBy(scrollOffset, resolve,
           targetRect.left + boundaryOffset, targetRect.top + boundaryOffset, touchSourceType, direction);
     } else {
       reject();
     }
   });
 }
 
+function pinchZoomInTarget(targetSelector, scale) {
+  return new Promise(function(resolve, reject) {
+    if (window.chrome && chrome.gpuBenchmarking) {
+      scrollPageIfNeeded(targetSelector, document);
+      var target = document.querySelector(targetSelector);
+      var targetRect = target.getBoundingClientRect();
+      chrome.gpuBenchmarking.pinchBy(scale, targetRect.left + (targetRect.width/2), targetRect.top + (targetRect.height/2), function() {
+        resolve();
+      });
+    } else {
+      reject();
+    }
+  });
+}
+
 // Pen inputs.
 function penMoveToDocument() {
   return new Promise(function(resolve, reject) {
     if (window.eventSender) {
       eventSender.mouseMoveTo(0, 0, [], "pen", 0);
       resolve();
     } else {
       reject();
     }
   });
@@ skipping 53 matching lines @@
 }
 
 {
   var pointerevent_automation = async_test("PointerEvent Automation");
   // Defined in every test and should return a promise that gets resolved when input is finished.
   inject_input().then(function() {
     pointerevent_automation.done();
   });
 }