SurfaceFlinger: throttle applications based on uid

Add the ability for SurfaceFlinger to be able to throttle down to
a divider of the refresh rate (i.e. for 30/45 for 90Hz)

Change-Id: I6bfd6f43ee1f30e771a136c558d8ae9a6d7fbe0f
Test: Manually via 1039 SF backdoor
Bug: 170502573
Bug: 169270763
Bug: 169271059
diff --git a/services/surfaceflinger/tests/unittests/RefreshRateConfigsTest.cpp b/services/surfaceflinger/tests/unittests/RefreshRateConfigsTest.cpp
index 1f6f166..4762fd4 100644
--- a/services/surfaceflinger/tests/unittests/RefreshRateConfigsTest.cpp
+++ b/services/surfaceflinger/tests/unittests/RefreshRateConfigsTest.cpp
@@ -1471,6 +1471,34 @@
     EXPECT_EQ(KernelIdleTimerAction::TurnOff, refreshRateConfigs->getIdleTimerAction());
 }
 
+TEST_F(RefreshRateConfigsTest, RefreshRateDividerForUnknownUid) {
+    auto refreshRateConfigs =
+            std::make_unique<RefreshRateConfigs>(m30_60_72_90_120Device,
+                                                 /*currentConfigId=*/HWC_CONFIG_ID_30);
+    EXPECT_EQ(1, refreshRateConfigs->getRefreshRateDividerForUid(1234));
+}
+
+TEST_F(RefreshRateConfigsTest, RefreshRateDividerForUid) {
+    auto refreshRateConfigs =
+            std::make_unique<RefreshRateConfigs>(m30_60_72_90_120Device,
+                                                 /*currentConfigId=*/HWC_CONFIG_ID_30);
+    const uid_t uid = 1234;
+    refreshRateConfigs->setPreferredRefreshRateForUid(uid, 30);
+    EXPECT_EQ(1, refreshRateConfigs->getRefreshRateDividerForUid(uid));
+
+    refreshRateConfigs->setCurrentConfigId(HWC_CONFIG_ID_60);
+    EXPECT_EQ(2, refreshRateConfigs->getRefreshRateDividerForUid(uid));
+
+    refreshRateConfigs->setCurrentConfigId(HWC_CONFIG_ID_72);
+    EXPECT_EQ(1, refreshRateConfigs->getRefreshRateDividerForUid(uid));
+
+    refreshRateConfigs->setCurrentConfigId(HWC_CONFIG_ID_90);
+    EXPECT_EQ(3, refreshRateConfigs->getRefreshRateDividerForUid(uid));
+
+    refreshRateConfigs->setCurrentConfigId(HWC_CONFIG_ID_120);
+    EXPECT_EQ(4, refreshRateConfigs->getRefreshRateDividerForUid(uid));
+}
+
 } // namespace
 } // namespace scheduler
 } // namespace android