[sensors] Add Permission guard to the generic sensor apis.

third_party/WebKit/Source/modules/sensor/SensorProxy.cpp

Index: third_party/WebKit/Source/modules/sensor/SensorProxy.cpp
diff --git a/third_party/WebKit/Source/modules/sensor/SensorProxy.cpp b/third_party/WebKit/Source/modules/sensor/SensorProxy.cpp
index add04b99327deacdb576b82b73261f851d955c05..c0e4a390620f10581a45ee9276639b38a74fa4c2 100644
--- a/third_party/WebKit/Source/modules/sensor/SensorProxy.cpp
+++ b/third_party/WebKit/Source/modules/sensor/SensorProxy.cpp
@@ -5,24 +5,99 @@
 #include "modules/sensor/SensorProxy.h"
 
 #include "core/frame/LocalFrame.h"
+#include "modules/permissions/PermissionUtils.h"
 #include "modules/sensor/SensorProviderProxy.h"
+#include "platform/UserGestureIndicator.h"
 #include "platform/mojo/MojoHelper.h"
 #include "public/platform/Platform.h"
+#include "wtf/RefPtr.h"
 
 using namespace device::mojom::blink;
 
 namespace blink {
 
-SensorProxy::SensorProxy(SensorType sensorType, SensorProviderProxy* provider)
+using mojom::blink::PermissionName;
+using mojom::blink::PermissionService;
+using mojom::blink::PermissionStatus;
+
+SensorProxy::SensorProxy(SensorType sensorType,
+                         ExecutionContext* executionContext,
+                         SensorProviderProxy* provider)
     : m_type(sensorType),
       m_mode(ReportingMode::CONTINUOUS),
       m_provider(provider),
       m_clientBinding(this),
       m_state(SensorProxy::Uninitialized),
       m_reading(),
-      m_suspended(false) {}
+      m_suspended(false),
+      m_sensorPermission(PermissionStatus::ASK),
+      m_executionContext(executionContext) {
+  // Get permission service.

[shalamov, 2016/11/04 19:00:20]

Is this needed in constructor? Also, handleSersonError will go through all
observers (JS instances) and notify them, so line 39 doesn't do anything, since
there can't be any observers at this point.

[riju_, 2016/11/09 10:30:34]

Moving to Initialize

+  PermissionService* permissionService =
+      getPermissionService(m_executionContext);
+  if (!permissionService) {
+    handleSensorError(
+        InvalidStateError,
+        "In its current state, the global scope can't request permissions");
+  }
+
+  // Check permissions.
+  m_permissionService->HasPermission(
+      createPermissionDescriptor(PermissionName::SENSORS),
+      m_executionContext->getSecurityOrigin(),
+      convertToBaseCallback(
+          WTF::bind(&SensorProxy::onPermissionUpdate, wrapPersistent(this))));
+}
+
+void SensorProxy::getNextPermissionChange(ExecutionContext* executionContext,
+                                          PermissionStatus status) {
+  m_permissionService->GetNextPermissionChange(
+      createPermissionDescriptor(PermissionName::SENSORS),
+      executionContext->getSecurityOrigin(), m_sensorPermission,
+      convertToBaseCallback(
+          WTF::bind(&SensorProxy::onPermissionUpdate, wrapPersistent(this))));
+}
 
-SensorProxy::~SensorProxy() {}
+void SensorProxy::requestPermission(ExecutionContext* executionContext,
+                                    PermissionStatus status) {
+  m_permissionService->RequestPermission(
+      createPermissionDescriptor(PermissionName::SENSORS),
+      m_executionContext->getSecurityOrigin(),
+      UserGestureIndicator::processingUserGesture(),
+      convertToBaseCallback(
+          WTF::bind(&SensorProxy::onPermissionUpdate, wrapPersistent(this))));
+}
+
+void SensorProxy::onPermissionUpdate(PermissionStatus status) {
+  if (m_sensorPermission != status) {
+    m_sensorPermission = status;
+    SensorPermissionChanged();
+  }
+}
+
+SensorProxy::~SensorProxy() {
+  m_permissionService.reset();

[Mikhail, 2016/11/07 08:02:02]

isn't it automatically reset when destructed?

[riju_, 2016/11/09 10:30:34]

Done.

+}
+
+void SensorProxy::resetPermissionService() {
+  m_permissionService.reset();
+}
+
+PermissionService* SensorProxy::getPermissionService(
+    ExecutionContext* executionContext) {
+  if (!m_permissionService &&
+      connectToPermissionService(executionContext,
+                                 mojo::GetProxy(&m_permissionService))) {
+    m_permissionService.set_connection_error_handler(convertToBaseCallback(
+        WTF::bind(&SensorProxy::permissionServiceConnectionError,
+                  wrapWeakPersistent(this))));
+  }
+  return m_permissionService.get();
+}
+
+void SensorProxy::permissionServiceConnectionError() {
+  m_permissionService.reset();
+}
 
 void SensorProxy::dispose() {
   m_clientBinding.Close();
@@ -31,6 +106,7 @@ void SensorProxy::dispose() {
 DEFINE_TRACE(SensorProxy) {
   visitor->trace(m_observers);
   visitor->trace(m_provider);
+  visitor->trace(m_executionContext);
 }
 
 void SensorProxy::addObserver(Observer* observer) {
@@ -119,6 +195,11 @@ void SensorProxy::SensorReadingChanged() {
     observer->onSensorReadingChanged();
 }
 
+void SensorProxy::SensorPermissionChanged() {
+  for (Observer* observer : m_observers)
+    observer->onSensorPermissionChanged();
+}
+
 void SensorProxy::handleSensorError(ExceptionCode code,
                                     const String& sanitizedMessage,
                                     const String& unsanitizedMessage) {
@@ -132,6 +213,7 @@ void SensorProxy::handleSensorError(ExceptionCode code,
   m_sharedBufferHandle.reset();
   m_defaultConfig.reset();
   m_clientBinding.Close();
+  m_permissionService.reset();
 
   for (Observer* observer : m_observers)
     observer->onSensorError(code, sanitizedMessage, unsanitizedMessage);
@@ -168,6 +250,10 @@ void SensorProxy::onSensorCreated(SensorInitParamsPtr params,
     return;
   }
 
+  // Check permission now.
+  if (m_sensorPermission == PermissionStatus::ASK)
+    requestPermission(m_executionContext, m_sensorPermission);

[Mikhail, 2016/11/04 13:05:59]

here it's a bit late to check permission as sensor is already created.

I'd move permissions check to 'initialize' before we start any other actions.

[riju_, 2016/11/09 10:30:34]

Done.

+
   auto errorCallback =
       WTF::bind(&SensorProxy::handleSensorError, wrapWeakPersistent(this),
                 UnknownError, String("Internal error"), String());