Don't add FillEventHistory events to the wrong session.

The AutofillSession.getFillEventHistory() method returns only the event history
for the last onFillRequest(). In the scenario where the user switches
activities and the server has multiple sessions open, only the events for the
last session should be recorded.

Test: existing CtsAutoFillServiceTestCases pass
Test: LoginActivityTest.checkFillSelectionFromPreviousSessionIsDiscarded

Fixes: 62802026

Change-Id: I447ed77c2167095867b35d616b5cf2ae43aa28db

core/java/android/service/autofill/FillEventHistory.java

@@ -54,6 +54,11 @@ public final class FillEventHistory implements Parcelable {
      */
     private final int mServiceUid;
 
+    /**
+     * Not in parcel. The ID of the autofill session that created the {@link FillResponse}.
+     */
+    private final int mSessionId;
+
     @Nullable private final Bundle mClientState;
     @Nullable List<Event> mEvents;
 
@@ -68,6 +73,11 @@ public final class FillEventHistory implements Parcelable {
         return mServiceUid;
     }
 
+    /** @hide */
+    public int getSessionId() {
+        return mSessionId;
+    }
+
     /**
      * Returns the client state set in the previous {@link FillResponse}.
      *
@@ -102,9 +112,10 @@ public final class FillEventHistory implements Parcelable {
     /**
      * @hide
      */
-    public FillEventHistory(int serviceUid, @Nullable Bundle clientState) {
+    public FillEventHistory(int serviceUid, int sessionId, @Nullable Bundle clientState) {
         mClientState = clientState;
         mServiceUid = serviceUid;
+        mSessionId = sessionId;
     }
 
     @Override
@@ -205,7 +216,7 @@ public final class FillEventHistory implements Parcelable {
             new Parcelable.Creator<FillEventHistory>() {
                 @Override
                 public FillEventHistory createFromParcel(Parcel parcel) {
-                    FillEventHistory selection = new FillEventHistory(0, parcel.readBundle());
+                    FillEventHistory selection = new FillEventHistory(0, 0, parcel.readBundle());
 
                     int numEvents = parcel.readInt();
                     for (int i = 0; i < numEvents; i++) {