DeepLab V3 demo on Android

Moved the project from [ExecuTorch](https://github.com/pytorch/executorch/tree/refs/tags/v0.5.0-rc3/examples/demo-apps/android/ExecuTorchDemo).

Add the script to export the model and run the model on python.

Add the instrumentation test for android.

Author: kirklandsign

dl3/android/DeepLabV3Demo/.gitignore

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+*.iml
+.gradle
+/local.properties
+.idea
+.DS_Store
+/build
+/captures
+.externalNativeBuild
+.cxx
+local.properties
+*.so

dl3/android/DeepLabV3Demo/README.md

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+# ExecuTorch Android Demo App
+
+This guide explains how to setup ExecuTorch for Android using a demo app. The app employs a [DeepLab v3](https://pytorch.org/hub/pytorch_vision_deeplabv3_resnet101/) model for image segmentation tasks. Models are exported to ExecuTorch using [XNNPACK FP32 backend](https://pytorch.org/executorch/main/backends-xnnpack.html#xnnpack-backend).
+
+## Prerequisites
+* Download and install [Android Studio and SDK 34](https://developer.android.com/studio).
+* (For exporting the DL3 model) Python 3.10+ with `executorch` package installed.
+
+## Exporting the model
+Run the script in `dl3/python/export.py` to export the model.
+
+## Push the model to the phone
+The app loads a hardcoded model path (`/data/local/tmp/dl3_xnnpack_fp32.pte`) on the phone.
+Run the following adb command to push the model.
+```
+adb push dl3_xnnpack_fp32.pte /data/local/tmp/dl3_xnnpack_fp32.pte
+```
+
+## Build and install to your phone
+(`cd dl3/android/DeepLanV3Demo` first)
+```
+./gradlew installDebug
+```
+
+## Run unit test
+```
+./gradlew connectedAndroidTest
+```

dl3/android/DeepLabV3Demo/app/.gitignore

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+/build

dl3/android/DeepLabV3Demo/app/build.gradle.kts

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+/*
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+plugins {
+  id("com.android.application")
+  id("org.jetbrains.kotlin.android")
+}
+
+android {
+  namespace = "org.pytorch.executorchexamples.dl3"
+  compileSdk = 34
+
+  defaultConfig {
+    applicationId = "org.pytorch.executorchexamples.dl3"
+    minSdk = 24
+    targetSdk = 34
+    versionCode = 1
+    versionName = "1.0"
+
+    testInstrumentationRunner = "androidx.test.runner.AndroidJUnitRunner"
+    vectorDrawables { useSupportLibrary = true }
+  }
+
+  buildTypes {
+    release {
+      isMinifyEnabled = false
+      proguardFiles(getDefaultProguardFile("proguard-android-optimize.txt"), "proguard-rules.pro")
+    }
+  }
+  compileOptions {
+    sourceCompatibility = JavaVersion.VERSION_1_8
+    targetCompatibility = JavaVersion.VERSION_1_8
+  }
+  kotlinOptions { jvmTarget = "1.8" }
+  buildFeatures { compose = true }
+  composeOptions { kotlinCompilerExtensionVersion = "1.4.3" }
+}
+
+dependencies {
+  implementation("androidx.appcompat:appcompat:1.7.0")
+  implementation("androidx.constraintlayout:constraintlayout:2.2.0")
+  implementation("org.pytorch:executorch-android:0.5.1")
+  testImplementation("junit:junit:4.13.2")
+  androidTestImplementation("androidx.test.ext:junit:1.1.5")
+  androidTestImplementation("androidx.test.espresso:espresso-core:3.5.1")
+  androidTestImplementation(platform("androidx.compose:compose-bom:2023.03.00"))
+  androidTestImplementation("androidx.compose.ui:ui-test-junit4")
+}

dl3/android/DeepLabV3Demo/app/proguard-rules.pro

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+# Add project specific ProGuard rules here.
+# You can control the set of applied configuration files using the
+# proguardFiles setting in build.gradle.
+#
+# For more details, see
+#   http://developer.android.com/guide/developing/tools/proguard.html
+
+# If your project uses WebView with JS, uncomment the following
+# and specify the fully qualified class name to the JavaScript interface
+# class:
+#-keepclassmembers class fqcn.of.javascript.interface.for.webview {
+#   public *;
+#}
+
+# Uncomment this to preserve the line number information for
+# debugging stack traces.
+#-keepattributes SourceFile,LineNumberTable
+
+# If you keep the line number information, uncomment this to
+# hide the original source file name.
+#-renamesourcefileattribute SourceFile

dl3/android/DeepLabV3Demo/app/src/androidTest/java/org/pytorch/executorchexamples/dl3/SanityCheck.java

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+/*
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+package org.pytorch.executorchexamples.dl3;
+
+import static org.junit.Assert.assertEquals;
+
+import androidx.test.filters.SmallTest;
+import org.junit.Test;
+import org.pytorch.executorch.Module;
+import org.pytorch.executorch.Tensor;
+
+@SmallTest
+public class SanityCheck {
+
+    @Test
+    public void testModuleForward() {
+        Module module = Module.load("/data/local/tmp/dl3_xnnpack_fp32.pte");
+        // Test with sample inputs (ones) and make sure there is no crash.
+        Tensor outputTensor = module.forward()[0].toTensor();
+        long[] shape = outputTensor.shape();
+        // batch_size * classes * width * height
+        assertEquals(4, shape.length);
+        assertEquals(1, shape[0]);
+        assertEquals(21, shape[1]);
+        assertEquals(224, shape[2]);
+        assertEquals(224, shape[3]);
+    }
+}

dl3/android/DeepLabV3Demo/app/src/main/AndroidManifest.xml

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+<?xml version="1.0" encoding="utf-8"?>
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools"
+    package="org.pytorch.executorchexamples.dl3">
+
+    <uses-sdk android:minSdkVersion="19"
+          android:targetSdkVersion="34"
+          android:maxSdkVersion="40" />
+
+    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
+
+    <application
+        android:allowBackup="false"
+        android:dataExtractionRules="@xml/data_extraction_rules"
+        android:fullBackupContent="@xml/backup_rules"
+        android:icon="@mipmap/ic_launcher"
+        android:label="@string/app_name"
+        android:roundIcon="@mipmap/ic_launcher_round"
+        android:supportsRtl="true"
+        android:theme="@style/Theme.DeepLabV3Demo"
+        android:extractNativeLibs="true"
+        tools:targetApi="34">
+
+        <activity
+            android:name=".MainActivity"
+            android:exported="true"
+            android:label="@string/app_name"
+            android:theme="@style/Theme.DeepLabV3Demo">
+            <intent-filter>
+                <action android:name="android.intent.action.MAIN" />
+                <category android:name="android.intent.category.LAUNCHER" />
+            </intent-filter>
+        </activity>
+    </application>
+
+</manifest>