Merge "JavaBBinder::onTransact - log if env null" am: b344dfaee9 am: 5aa2bac382 am: 16294cce9e

Original change: https://android-review.googlesource.com/c/platform/frameworks/base/+/2031503

Change-Id: Ib91786121409fc351d2969da48556e4000e04a99

core/jni/android_util_Binder.cpp

@@ -396,6 +396,9 @@ protected:
     {
         JNIEnv* env = javavm_to_jnienv(mVM);
 
+        LOG_ALWAYS_FATAL_IF(env == nullptr,
+                            "Binder thread started or Java binder used, but env null. Attach JVM?");
+
         ALOGV("onTransact() on %p calling object %p in env %p vm %p\n", this, mObject, env, mVM);
 
         IPCThreadState* thread_state = IPCThreadState::self();