Route drm@1.0-service.widevine libbinder to /dev/vndbinder

b/37309712: [Marlin/Sailfish] Fatal signal 6 (SIGABRT) when playing Exo
	    Player L1 encrypted content
Test: marlin

Change-Id: I05b12ea334138498be13bca92c9b1db6ed1b9870
Signed-off-by: Iliyan Malchev <malchev@google.com>

libwvdrmengine/Android.mk

@@ -24,6 +24,7 @@ LOCAL_SHARED_LIBRARIES := \
   liblog \
   libutils \
   libwvhidl \
+  libbinder \
 
 LOCAL_MODULE := android.hardware.drm@1.0-service.widevine
 LOCAL_INIT_RC := src_hidl/android.hardware.drm@1.0-service.widevine.rc

libwvdrmengine/src_hidl/service.cpp

@@ -21,6 +21,8 @@
 #include <android-base/logging.h>
 #include <hidl/HidlTransportSupport.h>
 
+#include <binder/ProcessState.h>
+
 using ::android::hardware::configureRpcThreadpool;
 using ::android::hardware::joinRpcThreadpool;
 using ::android::sp;
@@ -33,6 +35,10 @@ using wvdrm::hardware::drm::V1_0::widevine::WVDrmFactory;
 int main(int /* argc */, char** /* argv */) {
     ALOGD("android.hardware.drm@1.0-service.widevine starting...");
 
+    // The DRM HAL may communicate to other vendor components via
+    // /dev/vndbinder
+    android::ProcessState::initWithDriver("/dev/vndbinder");
+
     sp<IDrmFactory> drmFactory = new WVDrmFactory;
     sp<ICryptoFactory> cryptoFactory = new WVCryptoFactory;