SampleVideoEncoder: To encode AVC/HEVC stream with B-frames enabled

It uses MediaRecorder APIs to record B-frames enabled video from camera2
input and MediaCodec APIs to encode reference test vector using input surface.

Test: adb shell am start -n "com.android.media.samplevideoencoder/com.\
      android.media.samplevideoencoder.MainActivity"

Bug: 176060167

Change-Id: If0bae193c49a923d642a9bbc4aa0bb0b49670264
diff --git a/media/tests/SampleVideoEncoder/app/build.gradle b/media/tests/SampleVideoEncoder/app/build.gradle
new file mode 100644
index 0000000..cc54981
--- /dev/null
+++ b/media/tests/SampleVideoEncoder/app/build.gradle
@@ -0,0 +1,48 @@
+/*
+ * Copyright (C) 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+apply plugin: 'com.android.application'
+
+android {
+    compileSdkVersion 30
+    buildToolsVersion "30.0.2"
+
+    defaultConfig {
+        applicationId "com.android.media.samplevideoencoder"
+        minSdkVersion 24
+        targetSdkVersion 30
+        versionCode 1
+        versionName "1.0"
+        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
+    }
+
+    buildTypes {
+        release {
+            minifyEnabled false
+            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
+        }
+    }
+}
+
+dependencies {
+    implementation fileTree(dir: "libs", include: ["*.jar"])
+    implementation 'androidx.appcompat:appcompat:1.2.0'
+    implementation 'androidx.constraintlayout:constraintlayout:2.0.4'
+    testImplementation 'junit:junit:4.13.1'
+    androidTestImplementation 'androidx.test:runner:1.3.0'
+    androidTestImplementation 'androidx.test.ext:junit:1.1.2'
+    androidTestImplementation 'androidx.test.espresso:espresso-core:3.3.0'
+}
\ No newline at end of file