bluetooth: add BluetoothAdapter::IsPeripheralRoleSupported()

It appears that on Windows, Bluetooth hardware does not generally
support the BLE peripheral role (i.e. BLE advertisements). Add a method
to BluetoothAdapter that returns the
BluetoothAdapter.IsPeripheralRoleSupported property [0] on WinRT and
true everywhere else, so that client code can detect these cases.

[0]
https://docs.microsoft.com/en-us/uwp/api/windows.devices.bluetooth.bluetoothadapter.isperipheralrolesupported

Bug: 1069140
Change-Id: If8f2f448f30db6aaf720c10e00391dea3f65944e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2152892
Commit-Queue: Martin Kreichgauer <martinkr@chromium.org>
Reviewed-by: Reilly Grant <reillyg@chromium.org>
Cr-Commit-Position: refs/heads/master@{#759836}

device/bluetooth/bluetooth_adapter.cc

@@ -91,6 +91,11 @@ void BluetoothAdapter::SetPowered(bool powered,
   set_powered_callbacks_->error_callback = error_callback;
 }
 
+bool BluetoothAdapter::IsPeripheralRoleSupported() const {
+  // TODO(crbug/1071595): Implement this for more platforms.
+  return true;
+}
+
 std::unordered_map<BluetoothDevice*, BluetoothDevice::UUIDSet>
 BluetoothAdapter::RetrieveGattConnectedDevicesWithDiscoveryFilter(
     const BluetoothDiscoveryFilter& discovery_filter) {

device/bluetooth/bluetooth_adapter.h

@@ -433,6 +433,9 @@ class DEVICE_BLUETOOTH_EXPORT BluetoothAdapter
                           const base::Closure& callback,
                           const ErrorCallback& error_callback);
 
+  // Indicates whether the adapter support the LowEnergy peripheral role.
+  virtual bool IsPeripheralRoleSupported() const;
+
   // Indicates whether the adapter radio is discoverable.
   virtual bool IsDiscoverable() const = 0;
 

device/bluetooth/bluetooth_adapter_unittest.cc

@@ -765,6 +765,7 @@ TEST_F(BluetoothTest, MAYBE_ConstructFakeAdapter) {
   EXPECT_TRUE(adapter_->CanPower());
   EXPECT_TRUE(adapter_->IsPresent());
   EXPECT_TRUE(adapter_->IsPowered());
+  EXPECT_TRUE(adapter_->IsPeripheralRoleSupported());
   EXPECT_FALSE(adapter_->IsDiscoverable());
   EXPECT_FALSE(adapter_->IsDiscovering());
 }

device/bluetooth/bluetooth_adapter_winrt.cc

@@ -533,6 +533,16 @@ bool BluetoothAdapterWinrt::IsPowered() const {
   return GetState(radio_.Get()) == RadioState_On;
 }
 
+bool BluetoothAdapterWinrt::IsPeripheralRoleSupported() const {
+  boolean supported = false;
+  HRESULT hr = adapter_->get_IsPeripheralRoleSupported(&supported);
+  if (FAILED(hr)) {
+    BLUETOOTH_LOG(ERROR) << "Getting IsPeripheralRoleSupported failed: "
+                         << logging::SystemErrorCodeToString(hr);
+  }
+  return supported;
+}
+
 bool BluetoothAdapterWinrt::IsDiscoverable() const {
   NOTIMPLEMENTED();
   return false;

device/bluetooth/bluetooth_adapter_winrt.h

@@ -43,6 +43,7 @@ class DEVICE_BLUETOOTH_EXPORT BluetoothAdapterWinrt : public BluetoothAdapter {
   bool IsPresent() const override;
   bool CanPower() const override;
   bool IsPowered() const override;
+  bool IsPeripheralRoleSupported() const override;
   bool IsDiscoverable() const override;
   void SetDiscoverable(bool discoverable,
                        const base::Closure& callback,

device/bluetooth/test/fake_bluetooth_adapter_winrt.cc

@@ -73,7 +73,8 @@ HRESULT FakeBluetoothAdapterWinrt::get_IsLowEnergySupported(boolean* value) {
 
 HRESULT FakeBluetoothAdapterWinrt::get_IsPeripheralRoleSupported(
     boolean* value) {
-  return E_NOTIMPL;
+  *value = true;
+  return S_OK;
 }
 
 HRESULT FakeBluetoothAdapterWinrt::get_IsCentralRoleSupported(boolean* value) {