Allow null featureIds in AppOpsService binder calls

Bug: 136595429
Test: atest CtsAppOpsTestCases
Change-Id: I48713e962e3c3b60bd31ef134712a1d2f3da7cf5
diff --git a/libs/binder/IAppOpsService.cpp b/libs/binder/IAppOpsService.cpp
index 9760e13..b85a5f2 100644
--- a/libs/binder/IAppOpsService.cpp
+++ b/libs/binder/IAppOpsService.cpp
@@ -46,12 +46,14 @@
         return reply.readInt32();
     }
 
-    virtual int32_t noteOperation(int32_t code, int32_t uid, const String16& packageName) {
+    virtual int32_t noteOperation(int32_t code, int32_t uid, const String16& packageName,
+                const std::unique_ptr<String16>& featureId) {
         Parcel data, reply;
         data.writeInterfaceToken(IAppOpsService::getInterfaceDescriptor());
         data.writeInt32(code);
         data.writeInt32(uid);
         data.writeString16(packageName);
+        data.writeString16(featureId);
         remote()->transact(NOTE_OPERATION_TRANSACTION, data, &reply);
         // fail on exception
         if (reply.readExceptionCode() != 0) return MODE_ERRORED;
@@ -59,13 +61,15 @@
     }
 
     virtual int32_t startOperation(const sp<IBinder>& token, int32_t code, int32_t uid,
-                const String16& packageName, bool startIfModeDefault) {
+                const String16& packageName, const std::unique_ptr<String16>& featureId,
+                bool startIfModeDefault) {
         Parcel data, reply;
         data.writeInterfaceToken(IAppOpsService::getInterfaceDescriptor());
         data.writeStrongBinder(token);
         data.writeInt32(code);
         data.writeInt32(uid);
         data.writeString16(packageName);
+        data.writeString16(featureId);
         data.writeInt32(startIfModeDefault ? 1 : 0);
         remote()->transact(START_OPERATION_TRANSACTION, data, &reply);
         // fail on exception
@@ -74,13 +78,14 @@
     }
 
     virtual void finishOperation(const sp<IBinder>& token, int32_t code, int32_t uid,
-            const String16& packageName) {
+            const String16& packageName, const std::unique_ptr<String16>& featureId) {
         Parcel data, reply;
         data.writeInterfaceToken(IAppOpsService::getInterfaceDescriptor());
         data.writeStrongBinder(token);
         data.writeInt32(code);
         data.writeInt32(uid);
         data.writeString16(packageName);
+        data.writeString16(featureId);
         remote()->transact(FINISH_OPERATION_TRANSACTION, data, &reply);
     }
 
@@ -144,37 +149,16 @@
         remote()->transact(SET_CAMERA_AUDIO_RESTRICTION_TRANSACTION, data, &reply);
     }
 
-    virtual void noteAsyncOp(const String16& callingPackageName, int32_t uid,
-            const String16& packageName, int32_t opCode, const String16& featureId,
+    virtual void noteAsyncOp(const std::unique_ptr<String16>& callingPackageName, int32_t uid,
+            const String16& packageName, int32_t opCode, const std::unique_ptr<String16>& featureId,
             const String16& message) {
         Parcel data, reply;
         data.writeInterfaceToken(IAppOpsService::getInterfaceDescriptor());
-
-        // Convert empty callingPackage into null string
-        if (callingPackageName.size() != 0) {
-            data.writeString16(callingPackageName);
-        } else {
-            data.writeString16(nullptr, 0);
-        }
-
+        data.writeString16(callingPackageName);
         data.writeInt32(uid);
-
-        // Convert empty packageName into null string
-        if (packageName.size() != 0) {
-            data.writeString16(packageName);
-        } else {
-            data.writeString16(nullptr, 0);
-        }
-
+        data.writeString16(packageName);
         data.writeInt32(opCode);
-
-        // Convert empty featureId into null string
-        if (featureId.size() != 0) {
-            data.writeString16(featureId);
-        } else {
-            data.writeString16(nullptr, 0);
-        }
-
+        data.writeString16(featureId);
         data.writeString16(message);
         remote()->transact(NOTE_ASYNC_OP_TRANSACTION, data, &reply);
     }
@@ -217,7 +201,9 @@
             int32_t code = data.readInt32();
             int32_t uid = data.readInt32();
             String16 packageName = data.readString16();
-            int32_t res = noteOperation(code, uid, packageName);
+            std::unique_ptr<String16> featureId;
+            data.readString16(&featureId);
+            int32_t res = noteOperation(code, uid, packageName, featureId);
             reply->writeNoException();
             reply->writeInt32(res);
             return NO_ERROR;
@@ -228,8 +214,11 @@
             int32_t code = data.readInt32();
             int32_t uid = data.readInt32();
             String16 packageName = data.readString16();
+            std::unique_ptr<String16> featureId;
+            data.readString16(&featureId);
             bool startIfModeDefault = data.readInt32() == 1;
-            int32_t res = startOperation(token, code, uid, packageName, startIfModeDefault);
+            int32_t res = startOperation(token, code, uid, packageName, featureId,
+                    startIfModeDefault);
             reply->writeNoException();
             reply->writeInt32(res);
             return NO_ERROR;
@@ -240,7 +229,9 @@
             int32_t code = data.readInt32();
             int32_t uid = data.readInt32();
             String16 packageName = data.readString16();
-            finishOperation(token, code, uid, packageName);
+            std::unique_ptr<String16> featureId;
+            data.readString16(&featureId);
+            finishOperation(token, code, uid, packageName, featureId);
             reply->writeNoException();
             return NO_ERROR;
         } break;
@@ -296,11 +287,13 @@
         } break;
         case NOTE_ASYNC_OP_TRANSACTION: {
             CHECK_INTERFACE(IAppOpsService, data, reply);
-            String16 callingPackageName = data.readString16();
+            std::unique_ptr<String16> callingPackageName;
+            data.readString16(&callingPackageName);
             int32_t uid = data.readInt32();
             String16 packageName = data.readString16();
             int32_t opCode = data.readInt32();
-            String16 featureId = data.readString16();
+            std::unique_ptr<String16> featureId;
+            data.readString16(&featureId);
             String16 message = data.readString16();
             noteAsyncOp(callingPackageName, uid, packageName, opCode, featureId, message);
             reply->writeNoException();