test(app, android): handle missing sdcard better in test harness

if you use a non-play-store emulator, your sdcard may not always mount
in the emulator, and this test did not handle the android-storage-is-null
case well even though it is a legitimate case

Author: mikehardy

packages/app/e2e/utilsStatics.e2e.js

@@ -28,11 +28,23 @@ describe('utils()', function () {
       firebase.utils.FilePath.CACHES_DIRECTORY.should.be.a.String();
       firebase.utils.FilePath.DOCUMENT_DIRECTORY.should.be.a.String();
 
-      if (device.getPlatform() === 'android') {
+      // Even on android it may be null, skip if so
+      if (
+        device.getPlatform() === 'android' &&
+        firebase.utils.FilePath.EXTERNAL_DIRECTORY !== null
+      ) {
         firebase.utils.FilePath.EXTERNAL_DIRECTORY.should.be.a.String();
-        firebase.utils.FilePath.EXTERNAL_STORAGE_DIRECTORY.should.be.a.String();
       } else {
         should.equal(firebase.utils.FilePath.EXTERNAL_DIRECTORY, null);
+      }
+
+      // Even on android it may be null, skip if so
+      if (
+        device.getPlatform() === 'android' &&
+        firebase.utils.FilePath.EXTERNAL_STORAGE_DIRECTORY !== null
+      ) {
+        firebase.utils.FilePath.EXTERNAL_STORAGE_DIRECTORY.should.be.a.String();
+      } else {
         should.equal(firebase.utils.FilePath.EXTERNAL_STORAGE_DIRECTORY, null);
       }