Partially convert geolocation IPC to Mojo.

content/browser/geolocation/geolocation_service_impl.cc

+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "content/browser/geolocation/geolocation_service_impl.h"
+
+#include "base/bind.h"
+#include "base/metrics/histogram.h"
+#include "content/browser/geolocation/geolocation_service_impl_context.h"
+#include "content/public/common/mojo_geoposition.mojom.h"
+
+namespace content {
+
+namespace {
+
+// Geoposition error codes for reporting in UMA.
+enum GeopositionErrorCode {
+  // NOTE: Do not renumber these as that would confuse interpretation of
+  // previously logged data. When making changes, also update the enum list
+  // in tools/metrics/histograms/histograms.xml to keep it in sync.
+
+  // There was no error.
+  GEOPOSITION_ERROR_CODE_NONE = 0,
+
+  // User denied use of geolocation.
+  GEOPOSITION_ERROR_CODE_PERMISSION_DENIED = 1,
+
+  // Geoposition could not be determined.
+  GEOPOSITION_ERROR_CODE_POSITION_UNAVAILABLE = 2,
+
+  // Timeout.
+  GEOPOSITION_ERROR_CODE_TIMEOUT = 3,
+
+  // NOTE: Add entries only immediately above this line.
+  GEOPOSITION_ERROR_CODE_COUNT = 4
+};
+
+void RecordGeopositionErrorCode(Geoposition::ErrorCode error_code) {
+  GeopositionErrorCode code = GEOPOSITION_ERROR_CODE_NONE;
+  switch (error_code) {
+    case Geoposition::ERROR_CODE_NONE:
+      code = GEOPOSITION_ERROR_CODE_NONE;
+      break;
+    case Geoposition::ERROR_CODE_PERMISSION_DENIED:
+      code = GEOPOSITION_ERROR_CODE_PERMISSION_DENIED;
+      break;
+    case Geoposition::ERROR_CODE_POSITION_UNAVAILABLE:
+      code = GEOPOSITION_ERROR_CODE_POSITION_UNAVAILABLE;
+      break;
+    case Geoposition::ERROR_CODE_TIMEOUT:
+      code = GEOPOSITION_ERROR_CODE_TIMEOUT;
+      break;
+  }
+  UMA_HISTOGRAM_ENUMERATION("Geolocation.LocationUpdate.ErrorCode",
+                            code,
+                            GEOPOSITION_ERROR_CODE_COUNT);
+}
+
+}  // namespace
+
+// static
+void GeolocationServiceImpl::Create(
+    GeolocationServiceImplContext* context,
+    const base::Closure& on_location_update_callback,
+    mojo::InterfaceRequest<GeolocationService> request) {
+  GeolocationServiceImpl* service =
+      new GeolocationServiceImpl(context, on_location_update_callback);
+  BindToRequest(service, &request);
+}
+
+GeolocationServiceImpl::GeolocationServiceImpl(
+    GeolocationServiceImplContext* context,
+    const base::Closure& on_location_update_callback)
+    : context_(context),
+      on_location_update_callback_(on_location_update_callback) {
+  context_->AddService(this);
+}
+
+GeolocationServiceImpl::~GeolocationServiceImpl() {
+  context_->RemoveService(this);
+}
+
+void GeolocationServiceImpl::PauseUpdates() {
+  geolocation_subscription_.reset();
+}
+
+void GeolocationServiceImpl::ResumeUpdates() {
+  StartListeningForUpdates();
+}
+
+void GeolocationServiceImpl::StartListeningForUpdates() {
+  geolocation_subscription_ =
+      GeolocationProvider::GetInstance()->AddLocationUpdateCallback(
+          base::Bind(&GeolocationServiceImpl::OnLocationUpdate,
+                     base::Unretained(this)),
+          high_accuracy_);
+}
+
+void GeolocationServiceImpl::StartUpdating(bool high_accuracy) {
+  // TODO(blundell): What does this comment even mean?

[Michael van Ouwerkerk, 2014/10/08 14:13:07]

I was thinking the same. The purpose of this histogram is to check what %
geolocation requests is for high accuracy. I don't think an enable / disable
cycle affects that meaningfully, but it could be omitted as well, if we knew it
was due to e.g. page visibility going through a visible / hidden / visible
cycle.

[blundell, 2014/10/09 08:32:52]

I'm not sure what you're suggesting I do with the comment :). I'd be inclined to
just kill it.

+  // StartUpdating() can be invoked as a result of high-accuracy mode
+  // being enabled / disabled. No need to record the dispatcher again.
+  UMA_HISTOGRAM_BOOLEAN(
+      "Geolocation.GeolocationDispatcherHostImpl.EnableHighAccuracy",

[Michael van Ouwerkerk, 2014/10/08 14:13:08]

I've chosen a terrible name for this histogram. Still I'd rather not change it,
to avoid discontinuity in the data.

[blundell, 2014/10/09 08:32:52]

Acknowledged.

+      high_accuracy);
+  high_accuracy_ = high_accuracy;
+  StartListeningForUpdates();
+}
+
+void GeolocationServiceImpl::OnLocationUpdate(const Geoposition& position) {
+  RecordGeopositionErrorCode(position.error_code);
+  if (context_->paused())
+    return;
+
+  MojoGeopositionPtr geoposition(MojoGeoposition::New());
+  geoposition->valid = position.Validate();
+  geoposition->latitude = position.latitude;
+  geoposition->longitude = position.longitude;
+  geoposition->altitude = position.altitude;
+  geoposition->accuracy = position.accuracy;
+  geoposition->altitude_accuracy = position.altitude_accuracy;
+  geoposition->heading = position.heading;
+  geoposition->speed = position.speed;
+  geoposition->timestamp = position.timestamp.ToDoubleT();
+  geoposition->error_code = MojoGeoposition::ErrorCode(position.error_code);
+  geoposition->error_message = position.error_message;
+
+  on_location_update_callback_.Run();
+  client()->OnLocationUpdate(geoposition.Pass());
+}
+
+}  // namespace content