Fix talkback doesn't speak subtext info

In the original design, we only set title description for
view holder, this is wrong. It causes talkback can't
speak subtext info.

Currently, we set the title content description in the title
view directly, so talkback can say the title and subtext now
when talkback focus on an app view.

Test: Talkback speaks full information for an app entry
Fix: 177873163
Change-Id: I94996d596a85cc2813ed1b10cdd4ed2bee62f4a9

tests/robotests/src/com/android/settings/applications/manageapplications/ApplicationViewHolderTest.java

@@ -69,6 +69,22 @@ public class ApplicationViewHolderTest {
         assertThat(mHolder.mSummary.getText()).isEqualTo(mContext.getText(R.string.disabled));
     }
 
+    @Test
+    public void setTitle_titleIsNotEmptyAndContentIsNotEmpty_shouldSetTitleAndContentDescription() {
+        mHolder.setTitle("title", "content");
+
+        assertThat(mHolder.mAppName).isEqualTo("title");
+        assertThat(mHolder.mAppName.getContentDescription()).isEqualTo("content");
+    }
+
+    @Test
+    public void setTitle_titleIsNotEmptyButContentIsEmpty_shouldSetTitle() {
+        mHolder.setTitle("title", "");
+
+        assertThat(mHolder.mAppName).isEqualTo("title");
+        assertThat(mHolder.mAppName.getContentDescription()).isEqualTo("title");
+    }
+
     @Test
     public void updateSize() {
         final String invalidStr = "invalid";