InputTracer: Disallow adding new targets from a derived event tracker

There are complex interactions between features in InputDispatcher that
can lead to cancelations being generated for a derived event. When
this happens, calling dispatchToTargetHint will result in a crash.

Since it is difficult to determine exactly how to reproduce this issue
in a test case, loosen the check so that we only crash if we are trying
to add a new target, which should never happen.

Bug: 328928072
Bug: 210460522
Test: will re-enable the flag and wait for new crash reports
Change-Id: I0134a12b40e1da33a94d61b721e967dfdbc95fe8

1 files changed, 4 insertions, 3 deletions

diff --git a/services/inputflinger/dispatcher/trace/InputTracer.cpp b/services/inputflinger/dispatcher/trace/InputTracer.cpp
index 49e6e21828..4cf6a89db6 100644
--- a/services/inputflinger/dispatcher/trace/InputTracer.cpp
+++ b/services/inputflinger/dispatcher/trace/InputTracer.cpp
@@ -101,14 +101,15 @@ std::unique_ptr<EventTrackerInterface> InputTracer::createTrackerForSyntheticEve
 
 void InputTracer::dispatchToTargetHint(const EventTrackerInterface& cookie,
                                        const InputTarget& target) {
-    if (isDerivedCookie(cookie)) {
-        LOG(FATAL) << "Event target cannot be updated from a derived cookie.";
-    }
     auto& eventState = getState(cookie);
     if (eventState->isEventProcessingComplete) {
         // TODO(b/210460522): Disallow adding new targets after eventProcessingComplete() is called.
         return;
     }
+    if (isDerivedCookie(cookie)) {
+        // TODO(b/210460522): Disallow adding new targets from a derived cookie.
+        return;
+    }
     // TODO(b/210460522): Determine if the event is sensitive based on the target.
 }