[sensors] Fix flakiness in generic sensors tests

third_party/WebKit/LayoutTests/sensor/resources/sensor-helpers.js

 'use strict';
 
 // Wraps callback and calls reject_func if callback throws an error.
 class CallbackWrapper {
   constructor(callback, reject_func) {
     this.wrapper_func_ = (args) => {
       try {
         callback(args);
       } catch(e) {
         reject_func();
@@ skipping 35 matching lines @@
         this.remove_configuration_called_ = null;
         this.active_sensor_configurations_ = [];
         let rv = core.mapBuffer(handle, offset, size,
             core.MAP_BUFFER_FLAG_NONE);
         assert_equals(rv.result, core.RESULT_OK, "Failed to map shared buffer");
         this.buffer_array_ = rv.buffer;
         this.buffer_ = new Float64Array(this.buffer_array_);
         this.resetBuffer();
         bindings.StubBindings(this.stub_).delegate = this;
         bindings.StubBindings(this.stub_).connectionErrorHandler = () => {
-          reset();
+          this.reset();
         };
       }
 
       // Returns default configuration.
       getDefaultConfiguration() {
         return Promise.resolve({frequency: 5});
       }
 
       // Adds configuration for the sensor and starts reporting fake data
       // through update_reading_function_ callback.
@@ skipping 198 matching lines @@
           this.active_sensor_.client_ = proxy;
           }, sensor.SensorClient);
         return getSensorResponse(init_params, client_handle);
       }
 
       // Binds object to mojo message pipe
       bindToPipe(pipe) {
         this.stub_ = connection.bindHandleToStub(
             pipe, sensor_provider.SensorProvider);
         bindings.StubBindings(this.stub_).delegate = this;
+        bindings.StubBindings(this.stub_).connectionErrorHandler = () => {
+          this.reset();
+        };
       }
 
       // Mock functions
 
       // Resets state of mock SensorProvider between test runs.
       reset() {
         if (this.active_sensor_ != null) {
           this.active_sensor_.reset();
           this.active_sensor_ = null;
         }
 
         this.get_sensor_should_fail_ = false;
         this.resolve_func_ = null;
         this.max_frequency_ = 60;
+        if (this.stub_)
+          bindings.StubBindings(this.stub_).close();
       }
 
       // Sets flag that forces mock SensorProvider to fail when getSensor() is
       // invoked.
       setGetSensorShouldFail(should_fail) {
         this.get_sensor_should_fail_ = should_fail;
       }
 
       // Returns mock sensor that was created in getSensor to the layout test.
       getCreatedSensor() {
@@ skipping 41 matching lines @@
     };
 
     let onFailure = () => {
       sensor.mockSensorProvider.reset();
       return new Promise((resolve, reject) => { setTimeout(reject, 0); });
     };
 
     return Promise.resolve(func(sensor)).then(onSuccess, onFailure);
   }), name, properties);
 }