Check NULL for Drm object

Bug: 264629548
Test: CtsMediaDrmFrameworkTestCases
Change-Id: I1e9332898adc6a5268dfb107a2356d443e6f08ff
diff --git a/media/jni/android_media_MediaDrm.cpp b/media/jni/android_media_MediaDrm.cpp
index 681d76a..b70818d 100644
--- a/media/jni/android_media_MediaDrm.cpp
+++ b/media/jni/android_media_MediaDrm.cpp
@@ -1021,9 +1021,10 @@
 
 static jbyteArray android_media_MediaDrm_getSupportedCryptoSchemesNative(JNIEnv *env) {
     sp<IDrm> drm = android::DrmUtils::MakeDrm();
+    if (drm == NULL) return env->NewByteArray(0);
+
     std::vector<uint8_t> bv;
     drm->getSupportedSchemes(bv);
-
     jbyteArray jUuidBytes = env->NewByteArray(bv.size());
     env->SetByteArrayRegion(jUuidBytes, 0, bv.size(), reinterpret_cast<const jbyte *>(bv.data()));
     return jUuidBytes;