bluetooth: android: Fix a couple of crashes when adapter is turned on/off.

These changes fixes the crashes found when toggling the adapter on/off
when device chooser dialog is used in web-bluetooth.

BUG=570610

Review URL: https://codereview.chromium.org/1610053005

Cr-Commit-Position: refs/heads/master@{#374145}

7 files changed, 207 insertions, 23 deletions

diff --git a/device/bluetooth/android/java/src/org/chromium/device/bluetooth/ChromeBluetoothAdapter.java b/device/bluetooth/android/java/src/org/chromium/device/bluetooth/ChromeBluetoothAdapter.java
index 0774ea2..0a54a0b 100644
--- a/device/bluetooth/android/java/src/org/chromium/device/bluetooth/ChromeBluetoothAdapter.java
+++ b/device/bluetooth/android/java/src/org/chromium/device/bluetooth/ChromeBluetoothAdapter.java
@@ -111,6 +111,16 @@ final class ChromeBluetoothAdapter {
         return isPresent() && mAdapter.isEnabled();
     }
 
+    // Implements BluetoothAdapterAndroid::SetPowered.
+    @CalledByNative
+    private boolean setPowered(boolean powered) {
+        if (powered) {
+            return isPresent() && mAdapter.enable();
+        } else {
+            return isPresent() && mAdapter.disable();
+        }
+    }
+
     // Implements BluetoothAdapterAndroid::IsDiscoverable.
     @CalledByNative
     private boolean isDiscoverable() {
@@ -184,6 +194,10 @@ final class ChromeBluetoothAdapter {
     private boolean startScan() {
         Wrappers.BluetoothLeScannerWrapper scanner = mAdapter.getBluetoothLeScanner();
 
+        if (scanner == null) {
+            return false;
+        }
+
         if (!canScan()) {
             return false;
         }
@@ -199,6 +213,11 @@ final class ChromeBluetoothAdapter {
             scanner.startScan(null /* filters */, scanMode, mScanCallback);
         } catch (IllegalArgumentException e) {
             Log.e(TAG, "Cannot start scan: " + e);
+            mScanCallback = null;
+            return false;
+        } catch (IllegalStateException e) {
+            Log.e(TAG, "Adapter is off. Cannot start scan: " + e);
+            mScanCallback = null;
             return false;
         }
         return true;
@@ -212,12 +231,16 @@ final class ChromeBluetoothAdapter {
         if (mScanCallback == null) {
             return false;
         }
+
         try {
-            mAdapter.getBluetoothLeScanner().stopScan(mScanCallback);
+            Wrappers.BluetoothLeScannerWrapper scanner = mAdapter.getBluetoothLeScanner();
+            if (scanner != null) {
+                scanner.stopScan(mScanCallback);
+            }
         } catch (IllegalArgumentException e) {
             Log.e(TAG, "Cannot stop scan: " + e);
-            mScanCallback = null;
-            return false;
+        } catch (IllegalStateException e) {
+            Log.e(TAG, "Adapter is off. Cannot stop scan: " + e);
         }
         mScanCallback = null;
         return true;
diff --git a/device/bluetooth/android/java/src/org/chromium/device/bluetooth/Wrappers.java b/device/bluetooth/android/java/src/org/chromium/device/bluetooth/Wrappers.java
index 2ccdaae..9287f85 100644
--- a/device/bluetooth/android/java/src/org/chromium/device/bluetooth/Wrappers.java
+++ b/device/bluetooth/android/java/src/org/chromium/device/bluetooth/Wrappers.java
@@ -46,13 +46,15 @@ import java.util.UUID;
 class Wrappers {
     private static final String TAG = "Bluetooth";
 
+    public static final int DEVICE_CLASS_UNSPECIFIED = 0x1F00;
+
     /**
      * Wraps android.bluetooth.BluetoothAdapter.
      */
     static class BluetoothAdapterWrapper {
         private final BluetoothAdapter mAdapter;
         protected final ContextWrapper mContext;
-        protected final BluetoothLeScannerWrapper mScanner;
+        protected BluetoothLeScannerWrapper mScannerWrapper;
 
         /**
          * Creates a BluetoothAdapterWrapper using the default
@@ -94,34 +96,42 @@ class Wrappers {
                 Log.i(TAG, "BluetoothAdapterWrapper.create failed: Default adapter not found.");
                 return null;
             } else {
-                return new BluetoothAdapterWrapper(adapter, new ContextWrapper(context),
-                        new BluetoothLeScannerWrapper(adapter.getBluetoothLeScanner()));
+                return new BluetoothAdapterWrapper(adapter, new ContextWrapper(context));
             }
         }
 
-        public BluetoothAdapterWrapper(BluetoothAdapter adapter, ContextWrapper context,
-                BluetoothLeScannerWrapper scanner) {
+        public BluetoothAdapterWrapper(BluetoothAdapter adapter, ContextWrapper context) {
             mAdapter = adapter;
             mContext = context;
-            mScanner = scanner;
-        }
-
-        public ContextWrapper getContext() {
-            return mContext;
         }
 
-        public BluetoothLeScannerWrapper getBluetoothLeScanner() {
-            return mScanner;
+        public boolean disable() {
+            return mAdapter.disable();
         }
 
-        public boolean isEnabled() {
-            return mAdapter.isEnabled();
+        public boolean enable() {
+            return mAdapter.enable();
         }
 
         public String getAddress() {
             return mAdapter.getAddress();
         }
 
+        public BluetoothLeScannerWrapper getBluetoothLeScanner() {
+            BluetoothLeScanner scanner = mAdapter.getBluetoothLeScanner();
+            if (scanner == null) {
+                return null;
+            }
+            if (mScannerWrapper == null) {
+                mScannerWrapper = new BluetoothLeScannerWrapper(scanner);
+            }
+            return mScannerWrapper;
+        }
+
+        public ContextWrapper getContext() {
+            return mContext;
+        }
+
         public String getName() {
             return mAdapter.getName();
         }
@@ -133,6 +143,10 @@ class Wrappers {
         public boolean isDiscovering() {
             return mAdapter.isDiscovering();
         }
+
+        public boolean isEnabled() {
+            return mAdapter.isEnabled();
+        }
     }
 
     /**
@@ -155,7 +169,7 @@ class Wrappers {
      * Wraps android.bluetooth.BluetoothLeScanner.
      */
     static class BluetoothLeScannerWrapper {
-        private final BluetoothLeScanner mScanner;
+        protected final BluetoothLeScanner mScanner;
         private final HashMap<ScanCallbackWrapper, ForwardScanCallbackToWrapper> mCallbacks;
 
         public BluetoothLeScannerWrapper(BluetoothLeScanner scanner) {
@@ -276,6 +290,11 @@ class Wrappers {
         }
 
         public int getBluetoothClass_getDeviceClass() {
+            if (mDevice == null || mDevice.getBluetoothClass() == null) {
+                // BluetoothDevice.getBluetoothClass() returns null if adapter has been powered off.
+                // Return DEVICE_CLASS_UNSPECIFIED in these cases.
+                return DEVICE_CLASS_UNSPECIFIED;
+            }
             return mDevice.getBluetoothClass().getDeviceClass();
         }
 
diff --git a/device/bluetooth/bluetooth_adapter_android.cc b/device/bluetooth/bluetooth_adapter_android.cc
index 144ad52..00cead7 100644
--- a/device/bluetooth/bluetooth_adapter_android.cc
+++ b/device/bluetooth/bluetooth_adapter_android.cc
@@ -77,7 +77,12 @@ bool BluetoothAdapterAndroid::IsPowered() const {
 void BluetoothAdapterAndroid::SetPowered(bool powered,
                                          const base::Closure& callback,
                                          const ErrorCallback& error_callback) {
-  NOTIMPLEMENTED();
+  if (Java_ChromeBluetoothAdapter_setPowered(AttachCurrentThread(),
+                                             j_adapter_.obj(), powered)) {
+    callback.Run();
+  } else {
+    error_callback.Run();
+  }
 }
 
 bool BluetoothAdapterAndroid::IsDiscoverable() const {
diff --git a/device/bluetooth/bluetooth_adapter_unittest.cc b/device/bluetooth/bluetooth_adapter_unittest.cc
index 12351c9..45a5271 100644
--- a/device/bluetooth/bluetooth_adapter_unittest.cc
+++ b/device/bluetooth/bluetooth_adapter_unittest.cc
@@ -479,6 +479,43 @@ TEST_F(BluetoothTest, DiscoverySession) {
 }
 #endif  // defined(OS_ANDROID)
 
+// Android only: this test is specific for Android and should not be
+// enabled for other platforms.
+#if defined(OS_ANDROID)
+TEST_F(BluetoothTest, AdapterIllegalStateBeforeStartScan) {
+  if (!PlatformSupportsLowEnergy()) {
+    LOG(WARNING) << "Low Energy Bluetooth unavailable, skipping unit test.";
+    return;
+  }
+  InitWithFakeAdapter();
+  ForceIllegalStateException();
+  StartLowEnergyDiscoverySessionExpectedToFail();
+  EXPECT_EQ(0, callback_count_);
+  EXPECT_EQ(1, error_callback_count_);
+  EXPECT_FALSE(adapter_->IsDiscovering());
+}
+#endif  // defined(OS_ANDROID)
+
+// Android only: this test is specific for Android and should not be
+// enabled for other platforms.
+#if defined(OS_ANDROID)
+TEST_F(BluetoothTest, AdapterIllegalStateBeforeStopScan) {
+  if (!PlatformSupportsLowEnergy()) {
+    LOG(WARNING) << "Low Energy Bluetooth unavailable, skipping unit test.";
+    return;
+  }
+  InitWithFakeAdapter();
+  StartLowEnergyDiscoverySession();
+  EXPECT_EQ(1, callback_count_);
+  EXPECT_EQ(0, error_callback_count_);
+  EXPECT_TRUE(adapter_->IsDiscovering());
+  ForceIllegalStateException();
+  discovery_sessions_[0]->Stop(GetCallback(Call::EXPECTED),
+                               GetErrorCallback(Call::NOT_EXPECTED));
+  EXPECT_FALSE(adapter_->IsDiscovering());
+}
+#endif  // defined(OS_ANDROID)
+
 #if defined(OS_ANDROID) || defined(OS_MACOSX)
 // Checks that discovery fails (instead of hanging) when permissions are denied.
 TEST_F(BluetoothTest, NoPermissions) {
@@ -616,4 +653,52 @@ TEST_F(BluetoothTest, DiscoverMultipleLowEnergyDevices) {
 }
 #endif  // defined(OS_ANDROID) || defined(OS_MACOSX)
 
+#if defined(OS_ANDROID)
+TEST_F(BluetoothTest, TogglePowerFakeAdapter) {
+  InitWithFakeAdapter();
+  ASSERT_TRUE(adapter_->IsPresent());
+  ASSERT_TRUE(adapter_->IsPowered());
+
+  // Check if power can be turned off.
+  adapter_->SetPowered(false, GetCallback(Call::EXPECTED),
+                       GetErrorCallback(Call::NOT_EXPECTED));
+  EXPECT_FALSE(adapter_->IsPowered());
+
+  // Check if power can be turned on again.
+  adapter_->SetPowered(true, GetCallback(Call::EXPECTED),
+                       GetErrorCallback(Call::NOT_EXPECTED));
+  EXPECT_TRUE(adapter_->IsPowered());
+}
+#endif  // defined(OS_ANDROID)
+
+#if defined(OS_ANDROID)
+TEST_F(BluetoothTest, TogglePowerBeforeScan) {
+  InitWithFakeAdapter();
+  ASSERT_TRUE(adapter_->IsPresent());
+  ASSERT_TRUE(adapter_->IsPowered());
+
+  // Turn off adapter.
+  adapter_->SetPowered(false, GetCallback(Call::EXPECTED),
+                       GetErrorCallback(Call::NOT_EXPECTED));
+  ASSERT_FALSE(adapter_->IsPowered());
+
+  // Try to perform a scan.
+  StartLowEnergyDiscoverySessionExpectedToFail();
+
+  // Turn on adapter.
+  adapter_->SetPowered(true, GetCallback(Call::EXPECTED),
+                       GetErrorCallback(Call::NOT_EXPECTED));
+  ASSERT_TRUE(adapter_->IsPowered());
+
+  // Try to perform a scan again.
+  ResetEventCounts();
+  StartLowEnergyDiscoverySession();
+  EXPECT_EQ(1, callback_count_);
+  EXPECT_EQ(0, error_callback_count_);
+  EXPECT_TRUE(adapter_->IsDiscovering());
+  ASSERT_EQ((size_t)1, discovery_sessions_.size());
+  EXPECT_TRUE(discovery_sessions_[0]->IsActive());
+}
+#endif  // defined(OS_ANDROID)
+
 }  // namespace device
diff --git a/device/bluetooth/test/android/java/src/org/chromium/device/bluetooth/Fakes.java b/device/bluetooth/test/android/java/src/org/chromium/device/bluetooth/Fakes.java
index 65705fa..538f618 100644
--- a/device/bluetooth/test/android/java/src/org/chromium/device/bluetooth/Fakes.java
+++ b/device/bluetooth/test/android/java/src/org/chromium/device/bluetooth/Fakes.java
@@ -43,6 +43,7 @@ class Fakes {
     static class FakeBluetoothAdapter extends Wrappers.BluetoothAdapterWrapper {
         private final FakeContext mFakeContext;
         private final FakeBluetoothLeScanner mFakeScanner;
+        private boolean mPowered = true;
         final long mNativeBluetoothTestAndroid;
 
         /**
@@ -55,10 +56,10 @@ class Fakes {
         }
 
         private FakeBluetoothAdapter(long nativeBluetoothTestAndroid) {
-            super(null, new FakeContext(), new FakeBluetoothLeScanner());
+            super(null, new FakeContext());
             mNativeBluetoothTestAndroid = nativeBluetoothTestAndroid;
             mFakeContext = (FakeContext) mContext;
-            mFakeScanner = (FakeBluetoothLeScanner) mScanner;
+            mFakeScanner = new FakeBluetoothLeScanner();
         }
 
         @CalledByNative("FakeBluetoothAdapter")
@@ -71,6 +72,10 @@ class Fakes {
          */
         @CalledByNative("FakeBluetoothAdapter")
         public void discoverLowEnergyDevice(int deviceOrdinal) {
+            if (mFakeScanner == null) {
+                return;
+            }
+
             switch (deviceOrdinal) {
                 case 1: {
                     ArrayList<ParcelUuid> uuids = new ArrayList<ParcelUuid>(2);
@@ -115,11 +120,25 @@ class Fakes {
             }
         }
 
+        @CalledByNative("FakeBluetoothAdapter")
+        public void forceIllegalStateException() {
+            if (mFakeScanner != null) {
+                mFakeScanner.forceIllegalStateException();
+            }
+        }
+
         // -----------------------------------------------------------------------------------------
         // BluetoothAdapterWrapper overrides:
 
         @Override
-        public boolean isEnabled() {
+        public boolean disable() {
+            mPowered = false;
+            return true;
+        }
+
+        @Override
+        public boolean enable() {
+            mPowered = true;
             return true;
         }
 
@@ -129,6 +148,14 @@ class Fakes {
         }
 
         @Override
+        public Wrappers.BluetoothLeScannerWrapper getBluetoothLeScanner() {
+            if (isEnabled()) {
+                return mFakeScanner;
+            }
+            return null;
+        }
+
+        @Override
         public String getName() {
             return "FakeBluetoothAdapter";
         }
@@ -139,6 +166,11 @@ class Fakes {
         }
 
         @Override
+        public boolean isEnabled() {
+            return mPowered;
+        }
+
+        @Override
         public boolean isDiscovering() {
             return false;
         }
@@ -166,6 +198,7 @@ class Fakes {
      */
     static class FakeBluetoothLeScanner extends Wrappers.BluetoothLeScannerWrapper {
         public Wrappers.ScanCallbackWrapper mScanCallback;
+        private boolean mThrowException;
 
         private FakeBluetoothLeScanner() {
             super(null);
@@ -178,6 +211,9 @@ class Fakes {
                 throw new IllegalArgumentException(
                         "FakeBluetoothLeScanner does not support multiple scans.");
             }
+            if (mThrowException) {
+                throw new IllegalStateException("Adapter is off.");
+            }
             mScanCallback = callback;
         }
 
@@ -186,8 +222,15 @@ class Fakes {
             if (mScanCallback != callback) {
                 throw new IllegalArgumentException("No scan in progress.");
             }
+            if (mThrowException) {
+                throw new IllegalStateException("Adapter is off.");
+            }
             mScanCallback = null;
         }
+
+        void forceIllegalStateException() {
+            mThrowException = true;
+        }
     }
 
     /**
@@ -288,7 +331,7 @@ class Fakes {
 
         @Override
         public int getBluetoothClass_getDeviceClass() {
-            return 0x1F00; // Unspecified Device Class
+            return Wrappers.DEVICE_CLASS_UNSPECIFIED;
         }
 
         @Override
diff --git a/device/bluetooth/test/bluetooth_test_android.cc b/device/bluetooth/test/bluetooth_test_android.cc
index b31f5df..43299bc 100644
--- a/device/bluetooth/test/bluetooth_test_android.cc
+++ b/device/bluetooth/test/bluetooth_test_android.cc
@@ -81,6 +81,11 @@ BluetoothDevice* BluetoothTestAndroid::DiscoverLowEnergyDevice(
   return observer.last_device();
 }
 
+void BluetoothTestAndroid::ForceIllegalStateException() {
+  Java_FakeBluetoothAdapter_forceIllegalStateException(
+      AttachCurrentThread(), j_fake_bluetooth_adapter_.obj());
+}
+
 void BluetoothTestAndroid::SimulateGattConnection(BluetoothDevice* device) {
   BluetoothDeviceAndroid* device_android =
       static_cast<BluetoothDeviceAndroid*>(device);
diff --git a/device/bluetooth/test/bluetooth_test_android.h b/device/bluetooth/test/bluetooth_test_android.h
index 7f39099..3fb3a33 100644
--- a/device/bluetooth/test/bluetooth_test_android.h
+++ b/device/bluetooth/test/bluetooth_test_android.h
@@ -71,6 +71,10 @@ class BluetoothTestAndroid : public BluetoothTestBase {
   void SimulateGattDescriptorWriteWillFailSynchronouslyOnce(
       BluetoothGattDescriptor* descriptor) override;
 
+  // Instruct the fake adapter to throw an IllegalStateException for
+  // startScan and stopScan.
+  void ForceIllegalStateException();
+
   // Records that Java FakeBluetoothDevice connectGatt was called.
   void OnFakeBluetoothDeviceConnectGattCalled(
       JNIEnv* env,