Check in OSS NativeModule specs

Summary:
This diff checks in the output from `fbsource//xplat/js:FBReactNativeSpec-flow-type-android-files` into `react-native-github/ReactAndroid/src/main/java/com/facebook/fbreact/specs/`.

To update the codegen output, please run:
```
js1 build oss-native-modules-specs -p android
```

To use the codegen, add the following as a buck dep to your target:
```
fbsource//xplat/js/react-native-github/ReactAndroid/src/main/java/com/facebook/fbreact/specs:FBReactNativeSpecAndroid
```

Changelog: [Android][Added] Check in TurboModules codegen

Reviewed By: fkgozali

Differential Revision: D17990380

fbshipit-source-id: 94895e375311e9360c308dffadf1558a5ff04212

ReactAndroid/src/main/java/com/facebook/fbreact/specs/NativeDeviceEventManagerSpec.java

@@ -0,0 +1,28 @@
+/**
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * <p>This source code is licensed under the MIT license found in the LICENSE file in the root
+ * directory of this source tree.
+ *
+ * <p>Generated by an internal genrule from Flow types.
+ *
+ * @generated
+ * @nolint
+ */
+
+package com.facebook.fbreact.specs;
+
+import com.facebook.react.bridge.ReactApplicationContext;
+import com.facebook.react.bridge.ReactContextBaseJavaModule;
+import com.facebook.react.bridge.ReactMethod;
+import com.facebook.react.bridge.ReactModuleWithSpec;
+import com.facebook.react.turbomodule.core.interfaces.TurboModule;
+
+public abstract class NativeDeviceEventManagerSpec extends ReactContextBaseJavaModule implements ReactModuleWithSpec, TurboModule {
+  public NativeDeviceEventManagerSpec(ReactApplicationContext reactContext) {
+    super(reactContext);
+  }
+
+  @ReactMethod
+  public abstract void invokeDefaultBackPressHandler();
+}