Use the FuzzImplVSyncDispatch for fuzzing

This class seems to have been written for fuzzing, but it wasn't used
anywhere. Icdb80253436b4d0034fc20fcae8583efb7c30292 introduced new
attempts to use the VSyncDispatch, resulting in a null pointer
dereference in the fuzzer.

Override update, which is an abstract method added since this class was.

Ignore warnings for unused functions. surfaceflinger_scheduler_fuzzer.h
contains a static method, Now(), which is used by other code that pulls
in this header, but not by this executable.

Fixes: 270785319
Test: surfaceflinger_layer_fuzzer
Change-Id: I4e67e3f6383f466fbb092e7c7e9a0f867732c1f5

3 files changed, 9 insertions, 1 deletions

diff --git a/services/surfaceflinger/fuzzer/Android.bp b/services/surfaceflinger/fuzzer/Android.bp
index 7350e09cb5..f76a8d762a 100644
--- a/services/surfaceflinger/fuzzer/Android.bp
+++ b/services/surfaceflinger/fuzzer/Android.bp
@@ -69,6 +69,7 @@ cc_defaults {
         "-Wno-unused-result",
         "-Wno-conversion",
         "-Wno-sign-compare",
+        "-Wno-unused-function",
     ],
     fuzz_config: {
         cc: [
diff --git a/services/surfaceflinger/fuzzer/surfaceflinger_fuzzers_utils.h b/services/surfaceflinger/fuzzer/surfaceflinger_fuzzers_utils.h
index 6074bb7a16..c1bab0e89b 100644
--- a/services/surfaceflinger/fuzzer/surfaceflinger_fuzzers_utils.h
+++ b/services/surfaceflinger/fuzzer/surfaceflinger_fuzzers_utils.h
@@ -49,6 +49,7 @@
 #include "SurfaceFlingerDefaultFactory.h"
 #include "ThreadContext.h"
 #include "TimeStats/TimeStats.h"
+#include "surfaceflinger_scheduler_fuzzer.h"
 
 #include "renderengine/mock/RenderEngine.h"
 #include "scheduler/TimeKeeper.h"
@@ -237,7 +238,8 @@ public:
         const auto displayId = selectorPtr->getActiveMode().modePtr->getPhysicalDisplayId();
         registerDisplayInternal(displayId, std::move(selectorPtr),
                                 std::shared_ptr<VsyncSchedule>(
-                                        new VsyncSchedule(displayId, std::move(tracker), nullptr,
+                                        new VsyncSchedule(displayId, std::move(tracker),
+                                                          std::make_shared<FuzzImplVSyncDispatch>(),
                                                           std::move(controller))));
     }
 
diff --git a/services/surfaceflinger/fuzzer/surfaceflinger_scheduler_fuzzer.h b/services/surfaceflinger/fuzzer/surfaceflinger_scheduler_fuzzer.h
index e6be9a8b21..a32750e657 100644
--- a/services/surfaceflinger/fuzzer/surfaceflinger_scheduler_fuzzer.h
+++ b/services/surfaceflinger/fuzzer/surfaceflinger_scheduler_fuzzer.h
@@ -129,6 +129,11 @@ public:
         return (scheduler::ScheduleResult)0;
     }
 
+    scheduler::ScheduleResult update(CallbackToken /* token */,
+                                     ScheduleTiming /* scheduleTiming */) override {
+        return (scheduler::ScheduleResult)0;
+    }
+
     scheduler::CancelResult cancel(CallbackToken /* token */) override {
         return (scheduler::CancelResult)0;
     }