Add option to return a null Dagger graph

This allows processes that do not utilize the SysUI Dagger graph to
avoid having to subclass and instantiate it.

This change also makes the Screenshot cross-profile service take
advantage of this change.

Test: Turn on "Enable RequestProcessor" and "Enable Work Profile
Screenshots Policy" SysUI flags
Test: Take a screenshot of a work profile app
Test: Observe successful work profile screenshot
BUG: 259469497

Change-Id: I1a8c62ba079d90e575cab2a0e14b3f1466e1952c

packages/SystemUI/AndroidManifest.xml

@@ -416,6 +416,7 @@
 
         <service android:name=".screenshot.ScreenshotCrossProfileService"
                  android:permission="com.android.systemui.permission.SELF"
+                 android:process=":screenshot_cross_profile"
                  android:exported="false" />
 
         <service android:name=".screenrecord.RecordingService" />

packages/SystemUI/src/com/android/systemui/SystemUIInitializer.java

@@ -22,6 +22,8 @@ import android.os.Handler;
 import android.os.HandlerThread;
 import android.util.Log;
 
+import androidx.annotation.Nullable;
+
 import com.android.systemui.dagger.GlobalRootComponent;
 import com.android.systemui.dagger.SysUIComponent;
 import com.android.systemui.dagger.WMComponent;
@@ -53,6 +55,7 @@ public abstract class SystemUIInitializer {
         mContext = context;
     }
 
+    @Nullable
     protected abstract GlobalRootComponent.Builder getGlobalRootComponentBuilder();
 
     /**
@@ -69,6 +72,11 @@ public abstract class SystemUIInitializer {
      * Starts the initialization process. This stands up the Dagger graph.
      */
     public void init(boolean fromTest) throws ExecutionException, InterruptedException {
+        GlobalRootComponent.Builder globalBuilder = getGlobalRootComponentBuilder();
+        if (globalBuilder == null) {
+            return;
+        }
+
         mRootComponent = getGlobalRootComponentBuilder()
                 .context(mContext)
                 .instrumentationTest(fromTest)
@@ -119,6 +127,7 @@ public abstract class SystemUIInitializer {
                     .setBackAnimation(Optional.ofNullable(null))
                     .setDesktopMode(Optional.ofNullable(null));
         }
+
         mSysUIComponent = builder.build();
         if (initializeComponents) {
             mSysUIComponent.init();

packages/SystemUI/src/com/android/systemui/SystemUIInitializerImpl.kt

@@ -16,6 +16,7 @@
 
 package com.android.systemui
 
+import android.app.Application
 import android.content.Context
 import com.android.systemui.dagger.DaggerReferenceGlobalRootComponent
 import com.android.systemui.dagger.GlobalRootComponent
@@ -24,7 +25,17 @@ import com.android.systemui.dagger.GlobalRootComponent
  * {@link SystemUIInitializer} that stands up AOSP SystemUI.
  */
 class SystemUIInitializerImpl(context: Context) : SystemUIInitializer(context) {
-    override fun getGlobalRootComponentBuilder(): GlobalRootComponent.Builder {
-        return DaggerReferenceGlobalRootComponent.builder()
+
+    override fun getGlobalRootComponentBuilder(): GlobalRootComponent.Builder? {
+        return when (Application.getProcessName()) {
+            SCREENSHOT_CROSS_PROFILE_PROCESS -> null
+            else -> DaggerReferenceGlobalRootComponent.builder()
+        }
+    }
+
+    companion object {
+        private const val SYSTEMUI_PROCESS = "com.android.systemui"
+        private const val SCREENSHOT_CROSS_PROFILE_PROCESS =
+                "$SYSTEMUI_PROCESS:screenshot_cross_profile"
     }
 }