Merge "Revert "MediaCodec: don't cache buffers until requested"" into tm-dev am: 84959301fb

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/18894226

Change-Id: I61b1e17bb4d897ed09dbf26398a7ad8dc91766f5
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>

media/java/android/media/MediaCodec.java

@@ -2320,6 +2320,10 @@ final public class MediaCodec {
      */
     public final void start() {
         native_start();
+        synchronized(mBufferLock) {
+            cacheBuffers(true /* input */);
+            cacheBuffers(false /* input */);
+        }
     }
     private native final void native_start();
 
@@ -3950,9 +3954,6 @@ final public class MediaCodec {
                         + "Please obtain MediaCodec.LinearBlock or HardwareBuffer "
                         + "objects and attach to QueueRequest objects.");
             }
-            if (mCachedInputBuffers == null) {
-                cacheBuffers(true /* input */);
-            }
             if (mCachedInputBuffers == null) {
                 throw new IllegalStateException();
             }
@@ -3991,9 +3992,6 @@ final public class MediaCodec {
                         + "is not compatible with CONFIGURE_FLAG_USE_BLOCK_MODEL. "
                         + "Please use getOutputFrame to get output frames.");
             }
-            if (mCachedOutputBuffers == null) {
-                cacheBuffers(false /* input */);
-            }
             if (mCachedOutputBuffers == null) {
                 throw new IllegalStateException();
             }