Add example variablerateshading for Android (#1084)

[Why]
Example variablerateshading was not compiled for Android.

[How]
Generate Android version example variablerateshading from android/examples/_template.

android/examples/variablerateshading/build.gradle

@@ -0,0 +1,65 @@
+apply plugin: 'com.android.application'
+apply from: '../gradle/outputfilename.gradle'
+
+android {
+    compileSdkVersion rootProject.ext.compileSdkVersion
+    defaultConfig {
+        applicationId "de.saschawillems.vulkanVariablerateshading"
+        minSdkVersion rootProject.ext.minSdkVersion
+        targetSdkVersion rootProject.ext.targetSdkVersion
+        versionCode 1
+        versionName "1.0"
+        ndk {
+            abiFilters rootProject.ext.abiFilters
+        }
+        externalNativeBuild {
+            cmake {
+                cppFlags "-std=c++14"
+                arguments "-DANDROID_STL=c++_shared", '-DANDROID_TOOLCHAIN=clang'
+            }
+        }
+    }
+    sourceSets {
+        main.assets.srcDirs = ['assets']
+    }
+    buildTypes {
+        release {
+            minifyEnabled false
+            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
+        }
+    }
+    externalNativeBuild {
+        cmake {
+            path "CMakeLists.txt"
+        }
+    }
+}
+
+task copyTask {
+    copy {
+        from '../../common/res/drawable'
+        into "src/main/res/drawable"
+        include 'icon.png'
+    }
+
+    copy {
+        from rootProject.ext.shaderPath + 'glsl/base'
+        into 'assets/shaders/glsl/base'
+        include '*.spv'
+    }
+
+    copy {
+       from rootProject.ext.shaderPath + 'glsl/variablerateshading'
+       into 'assets/shaders/glsl/variablerateshading'
+       include '*.*'
+    }
+
+    copy {
+       from rootProject.ext.assetPath + 'models/sponza'
+       into 'assets/models/sponza'
+       include '*.*'
+    }
+
+}
+
+preBuild.dependsOn copyTask