Expose the testID to black-box testing frameworks on Android (#29610)

Summary:
There has been a long-standing issue where black-box testing frameworks like Appium and Xamarin UITest have not been able to access the `testID` view prop for Android (see #7135). A natural place for this to be exposed is via a view's `resource-id`. The `resource-id` is what I have used when working on UIAutomator-based tests for native Android apps and is a non-localized, development-only identifier. As mentioned in the linked ticket, you can dynamically set the resource-id using the view's AccessibilityNodeInfo. This change simply checks to see if a testID is provided for a view and then exposes it through the view's accessibility node delegate.

## Changelog

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[Android] [Fixed] - Fixes #7135,  #9942, and #16137. Display the `testID` as the `resource-id` for black-box testing frameworks

Pull Request resolved: #29610

Test Plan:
I used the `uiautomatorviewer` tool to verify that the resource-id is populated with the `testID` of a few different views of the RNTester app.
<img width="912" alt="Screen Shot 2020-08-10 at 3 38 27 PM" src="https://user-images.githubusercontent.com/875498/89838534-55044100-db20-11ea-9be2-ba507a81f6fb.png">
<img width="1096" alt="Screen Shot 2020-08-10 at 3 40 41 PM" src="https://user-images.githubusercontent.com/875498/89838542-5897c800-db20-11ea-9895-462c6fea1130.png">

Reviewed By: JoshuaGross

Differential Revision: D25799550

Pulled By: fkgozali

fbshipit-source-id: e64ff1b90fb66b427fce7af533aa94792cfbcad3

ReactAndroid/src/main/java/com/facebook/react/uimanager/ReactAccessibilityDelegate.java

@@ -246,6 +246,15 @@ public void onInitializeAccessibilityNodeInfo(View host, AccessibilityNodeInfoCo
         }
       }
     }
+
+    // Expose the testID prop as the resource-id name of the view. Black-box E2E/UI testing
+    // frameworks, which interact with the UI through the accessibility framework, do not have
+    // access to view tags. This allows developers/testers to avoid polluting the
+    // content-description with test identifiers.
+    final String testId = (String) host.getTag(R.id.react_test_id);
+    if (testId != null) {
+      info.setViewIdResourceName(testId);
+    }
   }
 
   @Override
@@ -425,7 +434,8 @@ public static void setDelegate(final View view) {
     if (!ViewCompat.hasAccessibilityDelegate(view)
         && (view.getTag(R.id.accessibility_role) != null
             || view.getTag(R.id.accessibility_state) != null
-            || view.getTag(R.id.accessibility_actions) != null)) {
+            || view.getTag(R.id.accessibility_actions) != null
+            || view.getTag(R.id.react_test_id) != null)) {
       ViewCompat.setAccessibilityDelegate(view, new ReactAccessibilityDelegate());
     }
   }