SF: Remove StrongTyping in favor of FTL mixins

Bug: 185536303
Test: presubmit
Change-Id: I1a14abc565c5995c36fdd98c9fd35502b2ccceee
diff --git a/services/surfaceflinger/Scheduler/EventThread.cpp b/services/surfaceflinger/Scheduler/EventThread.cpp
index ccd1c0f..96eccf2 100644
--- a/services/surfaceflinger/Scheduler/EventThread.cpp
+++ b/services/surfaceflinger/Scheduler/EventThread.cpp
@@ -148,7 +148,7 @@
     DisplayEventReceiver::Event event;
     event.header = {DisplayEventReceiver::DISPLAY_EVENT_MODE_CHANGE,
                     mode.modePtr->getPhysicalDisplayId(), systemTime()};
-    event.modeChange.modeId = mode.modePtr->getId().value();
+    event.modeChange.modeId = ftl::to_underlying(mode.modePtr->getId());
     event.modeChange.vsyncPeriod = mode.fps.getPeriodNsecs();
     return event;
 }
diff --git a/services/surfaceflinger/Scheduler/RefreshRateSelector.cpp b/services/surfaceflinger/Scheduler/RefreshRateSelector.cpp
index 7614453..eeca6be 100644
--- a/services/surfaceflinger/Scheduler/RefreshRateSelector.cpp
+++ b/services/surfaceflinger/Scheduler/RefreshRateSelector.cpp
@@ -286,7 +286,8 @@
 std::string RefreshRateSelector::Policy::toString() const {
     return base::StringPrintf("{defaultModeId=%d, allowGroupSwitching=%s"
                               ", primaryRanges=%s, appRequestRanges=%s}",
-                              defaultMode.value(), allowGroupSwitching ? "true" : "false",
+                              ftl::to_underlying(defaultMode),
+                              allowGroupSwitching ? "true" : "false",
                               to_string(primaryRanges).c_str(),
                               to_string(appRequestRanges).c_str());
 }
diff --git a/services/surfaceflinger/Scheduler/RefreshRateSelector.h b/services/surfaceflinger/Scheduler/RefreshRateSelector.h
index a1a7c28..6051e89 100644
--- a/services/surfaceflinger/Scheduler/RefreshRateSelector.h
+++ b/services/surfaceflinger/Scheduler/RefreshRateSelector.h
@@ -31,7 +31,6 @@
 
 #include "DisplayHardware/DisplayMode.h"
 #include "Scheduler/OneShotTimer.h"
-#include "Scheduler/StrongTyping.h"
 #include "ThreadContext.h"
 #include "Utils/Dumper.h"
 
diff --git a/services/surfaceflinger/Scheduler/StrongTyping.h b/services/surfaceflinger/Scheduler/StrongTyping.h
deleted file mode 100644
index a05c123..0000000
--- a/services/surfaceflinger/Scheduler/StrongTyping.h
+++ /dev/null
@@ -1,89 +0,0 @@
-/*
- * Copyright 2019 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-#pragma once
-namespace android {
-
-template <typename T, template <typename> class AbilityType>
-struct Ability {
-    T& base() { return static_cast<T&>(*this); }
-    T const& base() const { return static_cast<T const&>(*this); }
-};
-
-template <typename T>
-struct Add : Ability<T, Add> {
-    inline T operator+(T const& other) const { return T(this->base().value() + other.value()); }
-    inline T& operator++() {
-        ++this->base().value();
-        return this->base();
-    };
-    inline T operator++(int) {
-        T tmp(this->base());
-        operator++();
-        return tmp;
-    };
-    inline T& operator+=(T const& other) {
-        this->base().value() += other.value();
-        return this->base();
-    };
-};
-
-template <typename T>
-struct Compare : Ability<T, Compare> {
-    inline bool operator==(T const& other) const { return this->base().value() == other.value(); };
-    inline bool operator<(T const& other) const { return this->base().value() < other.value(); }
-    inline bool operator<=(T const& other) const { return (*this < other) || (*this == other); }
-    inline bool operator!=(T const& other) const { return !(*this == other); }
-    inline bool operator>=(T const& other) const { return !(*this < other); }
-    inline bool operator>(T const& other) const { return !(*this < other || *this == other); }
-};
-
-template <typename T>
-struct Hash : Ability<T, Hash> {
-    [[nodiscard]] std::size_t hash() const {
-        return std::hash<typename std::remove_const<
-                typename std::remove_reference<decltype(this->base().value())>::type>::type>{}(
-                this->base().value());
-    }
-};
-
-template <typename T, typename W, template <typename> class... Ability>
-struct StrongTyping : Ability<StrongTyping<T, W, Ability...>>... {
-    constexpr StrongTyping() = default;
-    constexpr explicit StrongTyping(T const& value) : mValue(value) {}
-    StrongTyping(StrongTyping const&) = default;
-    StrongTyping& operator=(StrongTyping const&) = default;
-    explicit inline operator T() const { return mValue; }
-    T const& value() const { return mValue; }
-    T& value() { return mValue; }
-
-    friend std::ostream& operator<<(std::ostream& os, const StrongTyping<T, W, Ability...>& value) {
-        return os << value.value();
-    }
-
-private:
-    T mValue{0};
-};
-} // namespace android
-
-namespace std {
-template <typename T, typename W, template <typename> class... Ability>
-struct hash<android::StrongTyping<T, W, Ability...>> {
-    std::size_t operator()(android::StrongTyping<T, W, Ability...> const& k) const {
-        return k.hash();
-    }
-};
-} // namespace std
diff --git a/services/surfaceflinger/Scheduler/VSyncDispatch.h b/services/surfaceflinger/Scheduler/VSyncDispatch.h
index 434fc36..ed8f8fe 100644
--- a/services/surfaceflinger/Scheduler/VSyncDispatch.h
+++ b/services/surfaceflinger/Scheduler/VSyncDispatch.h
@@ -20,10 +20,9 @@
 #include <optional>
 #include <string>
 
+#include <ftl/mixins.h>
 #include <utils/Timers.h>
 
-#include "StrongTyping.h"
-
 namespace android::scheduler {
 
 using ScheduleResult = std::optional<nsecs_t>;
@@ -35,7 +34,11 @@
  */
 class VSyncDispatch {
 public:
-    using CallbackToken = StrongTyping<size_t, class CallbackTokenTag, Compare>;
+    struct CallbackToken : ftl::DefaultConstructible<CallbackToken, size_t>,
+                           ftl::Equatable<CallbackToken>,
+                           ftl::Incrementable<CallbackToken> {
+        using DefaultConstructible::DefaultConstructible;
+    };
 
     virtual ~VSyncDispatch();
 
diff --git a/services/surfaceflinger/Scheduler/VSyncDispatchTimerQueue.cpp b/services/surfaceflinger/Scheduler/VSyncDispatchTimerQueue.cpp
index 98aa533..963f9e9 100644
--- a/services/surfaceflinger/Scheduler/VSyncDispatchTimerQueue.cpp
+++ b/services/surfaceflinger/Scheduler/VSyncDispatchTimerQueue.cpp
@@ -352,7 +352,7 @@
         Callback callback, std::string callbackName) {
     std::lock_guard lock(mMutex);
     return mCallbacks
-            .try_emplace(CallbackToken{++mCallbackToken},
+            .try_emplace(++mCallbackToken,
                          std::make_shared<VSyncDispatchTimerQueueEntry>(std::move(callbackName),
                                                                         std::move(callback),
                                                                         mMinVsyncDistance))
diff --git a/services/surfaceflinger/Scheduler/VSyncDispatchTimerQueue.h b/services/surfaceflinger/Scheduler/VSyncDispatchTimerQueue.h
index 30e5242..81c746e 100644
--- a/services/surfaceflinger/Scheduler/VSyncDispatchTimerQueue.h
+++ b/services/surfaceflinger/Scheduler/VSyncDispatchTimerQueue.h
@@ -158,7 +158,7 @@
     nsecs_t const mTimerSlack;
     nsecs_t const mMinVsyncDistance;
 
-    size_t mCallbackToken GUARDED_BY(mMutex) = 0;
+    CallbackToken mCallbackToken GUARDED_BY(mMutex);
 
     CallbackMap mCallbacks GUARDED_BY(mMutex);
     nsecs_t mIntendedWakeupTime GUARDED_BY(mMutex) = kInvalidTime;