Add finish() method to DataShare Read and Write Adapters

The finish() method is used to clear hard references after
the data copy has ended. This fixes a bug where the references are cleared before onError() is attempted to be called.

Test: CTS tests in followup CL
Bug: 157136368
Fixes: 157136368
Change-Id: If924fe388762831af90579e6b00bdf223230e203

core/java/android/service/contentcapture/ContentCaptureService.java

@@ -677,10 +677,6 @@ public abstract class ContentCaptureService extends Service {
                 throws RemoteException {
             synchronized (mLock) {
                 executeAdapterMethodLocked(adapter -> adapter.onStart(fd), "onStart");
-
-                // Client app and Service successfully connected, so this object would be kept alive
-                // until the session has finished.
-                clearHardReferences();
             }
         }
 
@@ -693,6 +689,13 @@ public abstract class ContentCaptureService extends Service {
             }
         }
 
+        @Override
+        public void finish() throws RemoteException {
+            synchronized (mLock) {
+                clearHardReferences();
+            }
+        }
+
         private void executeAdapterMethodLocked(Consumer<DataShareReadAdapter> adapterFn,
                 String methodName) {
             LocalDataShareAdapterResourceManager resourceManager = mResourceManagerReference.get();

core/java/android/service/contentcapture/IDataShareReadAdapter.aidl

@@ -22,4 +22,5 @@ import android.os.ICancellationSignal;
 oneway interface IDataShareReadAdapter {
     void start(in ParcelFileDescriptor fd);
     void error(int errorCode);
+    void finish();
 }

core/java/android/view/contentcapture/ContentCaptureManager.java

@@ -761,10 +761,6 @@ public final class ContentCaptureManager {
         public void write(ParcelFileDescriptor destination)
                 throws RemoteException {
             executeAdapterMethodLocked(adapter -> adapter.onWrite(destination), "onWrite");
-
-            // Client app and Service successfully connected, so this object would be kept alive
-            // until the session has finished.
-            clearHardReferences();
         }
 
         @Override
@@ -779,6 +775,11 @@ public final class ContentCaptureManager {
             clearHardReferences();
         }
 
+        @Override
+        public void finish() throws RemoteException  {
+            clearHardReferences();
+        }
+
         private void executeAdapterMethodLocked(Consumer<DataShareWriteAdapter> adapterFn,
                 String methodName) {
             LocalDataShareAdapterResourceManager resourceManager = mResourceManagerReference.get();

core/java/android/view/contentcapture/IDataShareWriteAdapter.aidl

@@ -25,4 +25,5 @@ oneway interface IDataShareWriteAdapter {
     void write(in ParcelFileDescriptor destination);
     void error(int errorCode);
     void rejected();
+    void finish();
 }