Tap suppression controller forwards the next TapCancel when the stashed TapDown is forwarded.

content/browser/renderer_host/input/tap_suppression_controller_unittest.cc

Index: content/browser/renderer_host/input/tap_suppression_controller_unittest.cc
diff --git a/content/browser/renderer_host/input/tap_suppression_controller_unittest.cc b/content/browser/renderer_host/input/tap_suppression_controller_unittest.cc
index 195a49629f03becb6f6160acb9805b2523c77eb6..b064a5bfb57b56e0d5019336d3997971a1dbd465 100644
--- a/content/browser/renderer_host/input/tap_suppression_controller_unittest.cc
+++ b/content/browser/renderer_host/input/tap_suppression_controller_unittest.cc
@@ -71,8 +71,10 @@ class MockTapSuppressionController : public TapSuppressionController,
   }
 
   void SendTapCancel() {
+    bool stashed_tap_down_forwarded =
+        last_actions_ & STASHED_TAP_DOWN_FORWARDED;
     last_actions_ = NONE;
-    if (ShouldSuppressTapEnd())
+    if (!stashed_tap_down_forwarded && ShouldSuppressTapEnd())
       last_actions_ |= TAP_CANCEL_SUPPRESSED;
     else
       last_actions_ |= TAP_CANCEL_FORWARDED;
@@ -245,7 +247,7 @@ TEST_F(TapSuppressionControllerTest, GFCAckBeforeTapSufficientlyLateTapUp) {
   EXPECT_EQ(MockTapSuppressionController::LAST_CANCEL_STOPPED_FLING,
             tap_suppression_controller_->state());
 
-  // Send MouseDown. This MouseDown should be suppressed, for now.
+  // Send TapDown. This TapDown should be suppressed, for now.
   tap_suppression_controller_->SendTapDown();
   EXPECT_EQ(MockTapSuppressionController::TAP_DOWN_DEFERRED,
             tap_suppression_controller_->last_actions());
@@ -270,6 +272,49 @@ TEST_F(TapSuppressionControllerTest, GFCAckBeforeTapSufficientlyLateTapUp) {
             tap_suppression_controller_->state());
 }
 
+// Test TapSuppressionController for when stashed TapDown gets forwarded.
+// The next TapCancel should be forwarded as well to maintain a valid input
+// stream.
+TEST_F(TapSuppressionControllerTest, GFCAckBeforeTapSufficientlyLateTapCancel) {
+  // Send GestureFlingCancel.
+  tap_suppression_controller_->SendGestureFlingCancel();
+  EXPECT_EQ(MockTapSuppressionController::NONE,
+            tap_suppression_controller_->last_actions());
+  EXPECT_EQ(MockTapSuppressionController::GFC_IN_PROGRESS,
+            tap_suppression_controller_->state());
+
+  // Send processed GestureFlingCancel Ack.
+  tap_suppression_controller_->SendGestureFlingCancelAck(true);
+  EXPECT_EQ(MockTapSuppressionController::NONE,
+            tap_suppression_controller_->last_actions());
+  EXPECT_EQ(MockTapSuppressionController::LAST_CANCEL_STOPPED_FLING,
+            tap_suppression_controller_->state());
+
+  // Send TapDown. This TapDown should be suppressed, for now.
+  tap_suppression_controller_->SendTapDown();
+  EXPECT_EQ(MockTapSuppressionController::TAP_DOWN_DEFERRED,
+            tap_suppression_controller_->last_actions());
+  EXPECT_EQ(MockTapSuppressionController::TAP_DOWN_STASHED,
+            tap_suppression_controller_->state());
+
+  // Wait more than the delay for TapDown timer. This should release the
+  // previously stashed TapDown.
+  tap_suppression_controller_->AdvanceTime(TimeDelta::FromMilliseconds(13));
+  EXPECT_EQ(MockTapSuppressionController::STASHED_TAP_DOWN_FORWARDED,
+            tap_suppression_controller_->last_actions());
+  EXPECT_EQ(MockTapSuppressionController::SUPPRESSING_TAPS,
+            tap_suppression_controller_->state());
+
+  // Send TapCancel. This TapCancel should be forwarded.
+  // When a TapDown is forwarded because of the timer expiration, the next
+  // TapCancel should get forwarded as well to maintain a valid input stream.
+  tap_suppression_controller_->SendTapCancel();
+  EXPECT_EQ(MockTapSuppressionController::TAP_CANCEL_FORWARDED,
+            tap_suppression_controller_->last_actions());
+  EXPECT_EQ(MockTapSuppressionController::SUPPRESSING_TAPS,
+            tap_suppression_controller_->state());
+}
+
 // Test TapSuppressionController for when GestureFlingCancel Ack comes before
 // TapDown, but there is a small delay between the Ack and TapDown.
 TEST_F(TapSuppressionControllerTest, GFCAckBeforeTapInsufficientlyLateTapDown) {