Use std::optional for @nullable (AIDL)

Previously, nullable types were mapped to std::unique_ptr for C++
backend. But std::unique_ptr typically involves unnecessary alloc/dealloc.

For example, if nullable string is represented in unique_ptr<string>, we
should do "unique_ptr<string>(new string(value))" to set a value.

To avoid breaking all hand-written parcelables, only new read/write
functions are added to Parcel class and they are used only by
aidl-generated code and their implementations.

Bug: 144773267
Test: build/flash/boot
      atest --test-mapping frameworks/native/libs/binder
Merged-In: I2c801e3b69f2f8ccf44267f15cbf79e1d8fbf19e
Change-Id: I2c801e3b69f2f8ccf44267f15cbf79e1d8fbf19e
(cherry picked from commit 149be4a25ef423491c73dfc7bfd95e8177e9b4f8)

Exempt-From-Owner-Approval: CP from master
diff --git a/cmds/installd/InstalldNativeService.h b/cmds/installd/InstalldNativeService.h
index df01c3c..8e22c3e 100644
--- a/cmds/installd/InstalldNativeService.h
+++ b/cmds/installd/InstalldNativeService.h
@@ -40,74 +40,74 @@
     static char const* getServiceName() { return "installd"; }
     virtual status_t dump(int fd, const Vector<String16> &args) override;
 
-    binder::Status createUserData(const std::unique_ptr<std::string>& uuid, int32_t userId,
+    binder::Status createUserData(const std::optional<std::string>& uuid, int32_t userId,
             int32_t userSerial, int32_t flags);
-    binder::Status destroyUserData(const std::unique_ptr<std::string>& uuid, int32_t userId,
+    binder::Status destroyUserData(const std::optional<std::string>& uuid, int32_t userId,
             int32_t flags);
 
-    binder::Status createAppData(const std::unique_ptr<std::string>& uuid,
+    binder::Status createAppData(const std::optional<std::string>& uuid,
             const std::string& packageName, int32_t userId, int32_t flags, int32_t appId,
             const std::string& seInfo, int32_t targetSdkVersion, int64_t* _aidl_return);
-    binder::Status restoreconAppData(const std::unique_ptr<std::string>& uuid,
+    binder::Status restoreconAppData(const std::optional<std::string>& uuid,
             const std::string& packageName, int32_t userId, int32_t flags, int32_t appId,
             const std::string& seInfo);
-    binder::Status migrateAppData(const std::unique_ptr<std::string>& uuid,
+    binder::Status migrateAppData(const std::optional<std::string>& uuid,
             const std::string& packageName, int32_t userId, int32_t flags);
-    binder::Status clearAppData(const std::unique_ptr<std::string>& uuid,
+    binder::Status clearAppData(const std::optional<std::string>& uuid,
             const std::string& packageName, int32_t userId, int32_t flags, int64_t ceDataInode);
-    binder::Status destroyAppData(const std::unique_ptr<std::string>& uuid,
+    binder::Status destroyAppData(const std::optional<std::string>& uuid,
             const std::string& packageName, int32_t userId, int32_t flags, int64_t ceDataInode);
 
-    binder::Status fixupAppData(const std::unique_ptr<std::string>& uuid, int32_t flags);
+    binder::Status fixupAppData(const std::optional<std::string>& uuid, int32_t flags);
 
-    binder::Status snapshotAppData(const std::unique_ptr<std::string>& volumeUuid,
+    binder::Status snapshotAppData(const std::optional<std::string>& volumeUuid,
             const std::string& packageName, const int32_t user, const int32_t snapshotId,
             int32_t storageFlags, int64_t* _aidl_return);
-    binder::Status restoreAppDataSnapshot(const std::unique_ptr<std::string>& volumeUuid,
+    binder::Status restoreAppDataSnapshot(const std::optional<std::string>& volumeUuid,
             const std::string& packageName, const int32_t appId, const std::string& seInfo,
             const int32_t user, const int32_t snapshotId, int32_t storageFlags);
-    binder::Status destroyAppDataSnapshot(const std::unique_ptr<std::string> &volumeUuid,
+    binder::Status destroyAppDataSnapshot(const std::optional<std::string> &volumeUuid,
             const std::string& packageName, const int32_t user, const int64_t ceSnapshotInode,
             const int32_t snapshotId, int32_t storageFlags);
 
-    binder::Status getAppSize(const std::unique_ptr<std::string>& uuid,
+    binder::Status getAppSize(const std::optional<std::string>& uuid,
             const std::vector<std::string>& packageNames, int32_t userId, int32_t flags,
             int32_t appId, const std::vector<int64_t>& ceDataInodes,
             const std::vector<std::string>& codePaths, std::vector<int64_t>* _aidl_return);
-    binder::Status getUserSize(const std::unique_ptr<std::string>& uuid,
+    binder::Status getUserSize(const std::optional<std::string>& uuid,
             int32_t userId, int32_t flags, const std::vector<int32_t>& appIds,
             std::vector<int64_t>* _aidl_return);
-    binder::Status getExternalSize(const std::unique_ptr<std::string>& uuid,
+    binder::Status getExternalSize(const std::optional<std::string>& uuid,
             int32_t userId, int32_t flags, const std::vector<int32_t>& appIds,
             std::vector<int64_t>* _aidl_return);
 
-    binder::Status getAppCrates(const std::unique_ptr<std::string>& uuid,
+    binder::Status getAppCrates(const std::optional<std::string>& uuid,
             const std::vector<std::string>& packageNames,
             int32_t userId,
-            std::unique_ptr<std::vector<std::unique_ptr<android::os::storage::CrateMetadata>>>*
+            std::optional<std::vector<std::optional<android::os::storage::CrateMetadata>>>*
                     _aidl_return);
     binder::Status getUserCrates(
-            const std::unique_ptr<std::string>& uuid, int32_t userId,
-            std::unique_ptr<std::vector<std::unique_ptr<android::os::storage::CrateMetadata>>>*
+            const std::optional<std::string>& uuid, int32_t userId,
+            std::optional<std::vector<std::optional<android::os::storage::CrateMetadata>>>*
                     _aidl_return);
 
-    binder::Status setAppQuota(const std::unique_ptr<std::string>& uuid,
+    binder::Status setAppQuota(const std::optional<std::string>& uuid,
             int32_t userId, int32_t appId, int64_t cacheQuota);
 
-    binder::Status moveCompleteApp(const std::unique_ptr<std::string>& fromUuid,
-            const std::unique_ptr<std::string>& toUuid, const std::string& packageName,
+    binder::Status moveCompleteApp(const std::optional<std::string>& fromUuid,
+            const std::optional<std::string>& toUuid, const std::string& packageName,
             int32_t appId, const std::string& seInfo,
             int32_t targetSdkVersion, const std::string& fromCodePath);
 
     binder::Status dexopt(const std::string& apkPath, int32_t uid,
-            const std::unique_ptr<std::string>& packageName, const std::string& instructionSet,
-            int32_t dexoptNeeded, const std::unique_ptr<std::string>& outputPath, int32_t dexFlags,
-            const std::string& compilerFilter, const std::unique_ptr<std::string>& uuid,
-            const std::unique_ptr<std::string>& classLoaderContext,
-            const std::unique_ptr<std::string>& seInfo, bool downgrade,
-            int32_t targetSdkVersion, const std::unique_ptr<std::string>& profileName,
-            const std::unique_ptr<std::string>& dexMetadataPath,
-            const std::unique_ptr<std::string>& compilationReason);
+            const std::optional<std::string>& packageName, const std::string& instructionSet,
+            int32_t dexoptNeeded, const std::optional<std::string>& outputPath, int32_t dexFlags,
+            const std::string& compilerFilter, const std::optional<std::string>& uuid,
+            const std::optional<std::string>& classLoaderContext,
+            const std::optional<std::string>& seInfo, bool downgrade,
+            int32_t targetSdkVersion, const std::optional<std::string>& profileName,
+            const std::optional<std::string>& dexMetadataPath,
+            const std::optional<std::string>& compilationReason);
 
     binder::Status compileLayouts(const std::string& apkPath, const std::string& packageName,
                                   const std::string& outDexFile, int uid, bool* _aidl_return);
@@ -130,9 +130,9 @@
             const std::string& profileName);
 
     binder::Status rmPackageDir(const std::string& packageDir);
-    binder::Status freeCache(const std::unique_ptr<std::string>& uuid, int64_t targetFreeBytes,
+    binder::Status freeCache(const std::optional<std::string>& uuid, int64_t targetFreeBytes,
             int64_t cacheReservedBytes, int32_t flags);
-    binder::Status linkNativeLibraryDirectory(const std::unique_ptr<std::string>& uuid,
+    binder::Status linkNativeLibraryDirectory(const std::optional<std::string>& uuid,
             const std::string& packageName, const std::string& nativeLibPath32, int32_t userId);
     binder::Status createOatDir(const std::string& oatDir, const std::string& instructionSet);
     binder::Status linkFile(const std::string& relativePath, const std::string& fromBase,
@@ -140,27 +140,27 @@
     binder::Status moveAb(const std::string& apkPath, const std::string& instructionSet,
             const std::string& outputPath);
     binder::Status deleteOdex(const std::string& apkPath, const std::string& instructionSet,
-            const std::unique_ptr<std::string>& outputPath);
+            const std::optional<std::string>& outputPath);
     binder::Status installApkVerity(const std::string& filePath,
             android::base::unique_fd verityInput, int32_t contentSize);
     binder::Status assertFsverityRootHashMatches(const std::string& filePath,
             const std::vector<uint8_t>& expectedHash);
     binder::Status reconcileSecondaryDexFile(const std::string& dexPath,
         const std::string& packageName, int32_t uid, const std::vector<std::string>& isa,
-        const std::unique_ptr<std::string>& volumeUuid, int32_t storage_flag, bool* _aidl_return);
+        const std::optional<std::string>& volumeUuid, int32_t storage_flag, bool* _aidl_return);
     binder::Status hashSecondaryDexFile(const std::string& dexPath,
-        const std::string& packageName, int32_t uid, const std::unique_ptr<std::string>& volumeUuid,
+        const std::string& packageName, int32_t uid, const std::optional<std::string>& volumeUuid,
         int32_t storageFlag, std::vector<uint8_t>* _aidl_return);
 
     binder::Status invalidateMounts();
-    binder::Status isQuotaSupported(const std::unique_ptr<std::string>& volumeUuid,
+    binder::Status isQuotaSupported(const std::optional<std::string>& volumeUuid,
             bool* _aidl_return);
-    binder::Status tryMountDataMirror(const std::unique_ptr<std::string>& volumeUuid);
-    binder::Status onPrivateVolumeRemoved(const std::unique_ptr<std::string>& volumeUuid);
+    binder::Status tryMountDataMirror(const std::optional<std::string>& volumeUuid);
+    binder::Status onPrivateVolumeRemoved(const std::optional<std::string>& volumeUuid);
 
     binder::Status prepareAppProfile(const std::string& packageName,
             int32_t userId, int32_t appId, const std::string& profileName,
-            const std::string& codePath, const std::unique_ptr<std::string>& dexMetadata,
+            const std::string& codePath, const std::optional<std::string>& dexMetadata,
             bool* _aidl_return);
 
     binder::Status migrateLegacyObbData();
@@ -177,7 +177,7 @@
     /* Map from UID to cache quota size */
     std::unordered_map<uid_t, int64_t> mCacheQuotas;
 
-    std::string findDataMediaPath(const std::unique_ptr<std::string>& uuid, userid_t userid);
+    std::string findDataMediaPath(const std::optional<std::string>& uuid, userid_t userid);
 };
 
 }  // namespace installd