Add support for writing byte arrays to parcels

b/13418320

Change-Id: I2285df9e9d3dc8a6a54055b13b352b81660bf45d

include/binder/Parcel.h

@@ -102,6 +102,7 @@ public:
     status_t            writeStrongBinder(const sp<IBinder>& val);
     status_t            writeWeakBinder(const wp<IBinder>& val);
     status_t            writeInt32Array(size_t len, const int32_t *val);
+    status_t            writeByteArray(size_t len, const uint8_t *val);
 
     template<typename T>
     status_t            write(const Flattenable<T>& val);

libs/binder/Parcel.cpp

@@ -628,6 +628,16 @@ status_t Parcel::writeInt32Array(size_t len, const int32_t *val) {
     }
     return ret;
 }
+status_t Parcel::writeByteArray(size_t len, const uint8_t *val) {
+    if (!val) {
+        return writeAligned(-1);
+    }
+    status_t ret = writeAligned(len);
+    if (ret == NO_ERROR) {
+        ret = write(val, len * sizeof(*val));
+    }
+    return ret;
+}
 
 status_t Parcel::writeInt64(int64_t val)
 {