[Sensors] Improvements in shared buffer managing

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

 'use strict';
 
 function sensor_mocks(mojo) {
   return define('Generic Sensor API mocks', [
     'mojo/public/js/core',
     'mojo/public/js/bindings',
     'mojo/public/js/connection',
     'device/generic_sensor/public/interfaces/sensor_provider.mojom',
     'device/generic_sensor/public/interfaces/sensor.mojom',
   ], (core, bindings, connection, sensor_provider, sensor) => {
@@ skipping 15 matching lines @@
         this.suspend_called_ = null;
         this.resume_called_ = null;
         this.add_configuration_called_ = null;
         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();
         };
       }
 
       // Returns default configuration.
       getDefaultConfiguration() {
         return Promise.resolve({frequency: 5});
       }
@@ skipping 67 matching lines @@
           window.clearTimeout(this.sensor_reading_timer_id_);
         }
 
         this.start_should_fail_ = false;
         this.sensor_reading_timer_id_ = null;
         this.active_sensor_configurations_ = [];
         this.suspend_called_ = null;
         this.resume_called_ = null;
         this.add_configuration_called_ = null;
         this.remove_configuration_called_ = null;
+        this.resetBuffer();
+      }
+
+      // Zeroes shared buffer.
+      resetBuffer() {
         for (let i = 0; i < this.buffer_.length; ++i) {
           this.buffer_[i] = 0;
         }
       }
 
       // Sets callback that is used to deliver sensor reading updates.
       setUpdateSensorReadingFunction(update_reading_function) {
         this.update_reading_function_ = update_reading_function;
         return Promise.resolve(this);
       }
@@ skipping 36 matching lines @@
     // Helper function that returns resolved promise for getSensor() function.
     function getSensorResponse(init_params, client_request) {
       return Promise.resolve({init_params, client_request});
     }
 
     // Class that mocks SensorProvider interface defined in
     // sensor_provider.mojom
     class MockSensorProvider {
       constructor() {
         this.reading_size_in_bytes_ =
-            sensor_provider.SensorInitParams.kReadBufferSize;
+            sensor_provider.SensorInitParams.kReadBufferSizeForTests;
         this.shared_buffer_size_in_bytes_ = this.reading_size_in_bytes_ *
                 sensor.SensorType.LAST;
         let rv =
                 core.createSharedBuffer(
                         this.shared_buffer_size_in_bytes_,
                         core.CREATE_SHARED_BUFFER_OPTIONS_FLAG_NONE);
         assert_equals(rv.result, core.RESULT_OK, "Failed to create buffer");
         this.shared_buffer_handle_ = rv.handle;
         this.active_sensor_ = null;
         this.get_sensor_should_fail_ = false;
@@ skipping 103 matching lines @@
   });
 }
 
 function sensor_test(func, name, properties) {
   mojo_test(mojo => sensor_mocks(mojo).then(sensor => {
     let result = Promise.resolve(func(sensor));
     let cleanUp = () => { sensor.mockSensorProvider.reset(); };
     return result.then(cleanUp, cleanUp);
   }), name, properties);
 }