From 4bc215c4101b9504c244356ad0264ea1f4912bbd Mon Sep 17 00:00:00 2001
From: Jernej Virag <jernej@google.com>
Date: Thu, 13 Jul 2023 16:59:29 +0200
Subject: [PATCH] Restore trimMemory behaviour from T

When we moved trimming code to ResourceTrimmer in I84637049a106a94bf9f06c5261c2941b55db4ba0, we also moved trimMemory(ComponentCallbacks2.TRIM_MEMORY_UI_HIDDEN) which happens after unlock from StatusBarKeyguardViewManager to the ResourceTrimmer behind a TRIM_FONT_CACHES_AT_UNLOCK flag.

Now that we've disabled TRIM_FONT_CACHES_AT_UNLOCK, this also disabled the trimMemory call we were doing since way before Android U.

To full restore pre-U trim font behaviour, this call should not be flag guarded behind the font caching flag.

Bug: 275486055
Bug: 290898642
Test: Updated unit tests
Change-Id: I677855fff144a53d212b65575111491c78803817
---
 .../systemui/keyguard/ResourceTrimmer.kt      | 54 +++++++++----------
 .../systemui/keyguard/ResourceTrimmerTest.kt  |  6 ++-
 2 files changed, 29 insertions(+), 31 deletions(-)

diff --git a/packages/SystemUI/src/com/android/systemui/keyguard/ResourceTrimmer.kt b/packages/SystemUI/src/com/android/systemui/keyguard/ResourceTrimmer.kt
index 1978b3d048b75..039460d8fdae8 100644
--- a/packages/SystemUI/src/com/android/systemui/keyguard/ResourceTrimmer.kt
+++ b/packages/SystemUI/src/com/android/systemui/keyguard/ResourceTrimmer.kt
@@ -61,28 +61,23 @@ constructor(
 
     override fun start() {
         Log.d(LOG_TAG, "Resource trimmer registered.")
-        if (
-            !(featureFlags.isEnabled(Flags.TRIM_RESOURCES_WITH_BACKGROUND_TRIM_AT_LOCK) ||
-                featureFlags.isEnabled(Flags.TRIM_FONT_CACHES_AT_UNLOCK))
-        ) {
-            return
-        }
-
-        applicationScope.launch(bgDispatcher) {
-            // We need to wait for the AoD transition (and animation) to complete.
-            // This means we're waiting for isDreaming (== implies isDoze) and dozeAmount == 1f
-            // signal. This is to make sure we don't clear font caches during animation which
-            // would jank and leave stale data in memory.
-            val isDozingFully =
-                keyguardInteractor.dozeAmount.map { it == 1f }.distinctUntilChanged()
-            combine(
-                    keyguardInteractor.wakefulnessModel.map { it.state },
-                    keyguardInteractor.isDreaming,
-                    isDozingFully,
-                    ::Triple
-                )
-                .distinctUntilChanged()
-                .collect { onWakefulnessUpdated(it.first, it.second, it.third) }
+        if (featureFlags.isEnabled(Flags.TRIM_RESOURCES_WITH_BACKGROUND_TRIM_AT_LOCK)) {
+            applicationScope.launch(bgDispatcher) {
+                // We need to wait for the AoD transition (and animation) to complete.
+                // This means we're waiting for isDreaming (== implies isDoze) and dozeAmount == 1f
+                // signal. This is to make sure we don't clear font caches during animation which
+                // would jank and leave stale data in memory.
+                val isDozingFully =
+                    keyguardInteractor.dozeAmount.map { it == 1f }.distinctUntilChanged()
+                combine(
+                        keyguardInteractor.wakefulnessModel.map { it.state },
+                        keyguardInteractor.isDreaming,
+                        isDozingFully,
+                        ::Triple
+                    )
+                    .distinctUntilChanged()
+                    .collect { onWakefulnessUpdated(it.first, it.second, it.third) }
+            }
         }
 
         applicationScope.launch(bgDispatcher) {
@@ -97,17 +92,16 @@ constructor(
 
     @WorkerThread
     private fun onKeyguardGone() {
-        if (!featureFlags.isEnabled(Flags.TRIM_FONT_CACHES_AT_UNLOCK)) {
-            return
-        }
-
-        if (DEBUG) {
-            Log.d(LOG_TAG, "Trimming font caches since keyguard went away.")
-        }
         // We want to clear temporary caches we've created while rendering and animating
         // lockscreen elements, especially clocks.
+        Log.d(LOG_TAG, "Sending TRIM_MEMORY_UI_HIDDEN.")
         globalWindowManager.trimMemory(ComponentCallbacks2.TRIM_MEMORY_UI_HIDDEN)
-        globalWindowManager.trimCaches(HardwareRenderer.CACHE_TRIM_FONT)
+        if (featureFlags.isEnabled(Flags.TRIM_FONT_CACHES_AT_UNLOCK)) {
+            if (DEBUG) {
+                Log.d(LOG_TAG, "Trimming font caches since keyguard went away.")
+            }
+            globalWindowManager.trimCaches(HardwareRenderer.CACHE_TRIM_FONT)
+        }
     }
 
     @WorkerThread
diff --git a/packages/SystemUI/tests/src/com/android/systemui/keyguard/ResourceTrimmerTest.kt b/packages/SystemUI/tests/src/com/android/systemui/keyguard/ResourceTrimmerTest.kt
index 925ac30b99fd7..05d6b99fe2275 100644
--- a/packages/SystemUI/tests/src/com/android/systemui/keyguard/ResourceTrimmerTest.kt
+++ b/packages/SystemUI/tests/src/com/android/systemui/keyguard/ResourceTrimmerTest.kt
@@ -16,6 +16,7 @@ import com.android.systemui.keyguard.shared.model.TransitionStep
 import com.android.systemui.keyguard.shared.model.WakeSleepReason
 import com.android.systemui.keyguard.shared.model.WakefulnessModel
 import com.android.systemui.keyguard.shared.model.WakefulnessState
+import com.android.systemui.util.mockito.any
 import com.android.systemui.utils.GlobalWindowManager
 import kotlinx.coroutines.ExperimentalCoroutinesApi
 import kotlinx.coroutines.test.TestScope
@@ -225,6 +226,9 @@ class ResourceTrimmerTest : SysuiTestCase() {
             keyguardTransitionRepository.sendTransitionStep(
                 TransitionStep(KeyguardState.LOCKSCREEN, KeyguardState.GONE)
             )
-            verifyNoMoreInteractions(globalWindowManager)
+            // Memory hidden should still be called.
+            verify(globalWindowManager, times(1))
+                .trimMemory(ComponentCallbacks2.TRIM_MEMORY_UI_HIDDEN)
+            verify(globalWindowManager, times(0)).trimCaches(any())
         }
 }