Fix getStreamVolumeDB for Android P and above

Bug: 163028167
Test: Locally on android Q device
Change-Id: I463f133981530e5ca936d62d6e1f10cb701e2e2f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2342579Reviewed-by: Luke Halliwell (slow) <halliwell@chromium.org>
Reviewed-by: Simeon Anfinrud <sanfin@chromium.org>
Commit-Queue: Rohan Parab <prohan@google.com>
Cr-Commit-Position: refs/heads/master@{#796002}

chromecast/media/cma/backend/android/java/src/org/chromium/chromecast/cma/backend/android/VolumeMap.java

@@ -94,6 +94,9 @@ public final class VolumeMap {
 
     // Returns the current volume in dB for the given stream type and volume index.
     private static float getStreamVolumeDB(int streamType, int idx) {
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.P) {
+            return getAudioManager().getStreamVolumeDb(streamType, idx, DEVICE_TYPE);
+        }
         float db = 0;
         if (Build.VERSION.SDK_INT == Build.VERSION_CODES.O_MR1
                 || Build.VERSION.SDK_INT == Build.VERSION_CODES.N) {
@@ -106,10 +109,6 @@ public final class VolumeMap {
             } catch (Exception e) {
                 Log.e(TAG, "Can not call AudioManager.getStreamVolumeDb():", e);
             }
-            // TODO(ckuiper): when Android P becomes available add something like this to call the
-            // AudioManager.getStreamVolumeDb() directly as it is public in P.
-            //   } else if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.P) {
-            //       db = sAudioManager.getStreamVolumeDb();
         } else {
             Log.e(TAG, "Unsupported Android SDK version:" + Build.VERSION.SDK_INT);
         }