Clear the Bitmap Pool when the UI is hidden on M+.

PiperOrigin-RevId: 259615959

Author: sjudd

library/src/main/java/com/bumptech/glide/load/engine/bitmap_recycle/LruBitmapPool.java

@@ -2,6 +2,7 @@
 
 import android.annotation.SuppressLint;
 import android.annotation.TargetApi;
+import android.content.ComponentCallbacks2;
 import android.graphics.Bitmap;
 import android.graphics.Color;
 import android.os.Build;
@@ -224,10 +225,12 @@ public void trimMemory(int level) {
     if (Log.isLoggable(TAG, Log.DEBUG)) {
       Log.d(TAG, "trimMemory, level=" + level);
     }
-    if (level >= android.content.ComponentCallbacks2.TRIM_MEMORY_BACKGROUND) {
+    if ((level >= ComponentCallbacks2.TRIM_MEMORY_BACKGROUND)
+        || ((Build.VERSION.SDK_INT >= Build.VERSION_CODES.M)
+            && (level >= ComponentCallbacks2.TRIM_MEMORY_UI_HIDDEN))) {
       clearMemory();
-    } else if (level >= android.content.ComponentCallbacks2.TRIM_MEMORY_UI_HIDDEN
-        || level == android.content.ComponentCallbacks2.TRIM_MEMORY_RUNNING_CRITICAL) {
+    } else if ((level >= ComponentCallbacks2.TRIM_MEMORY_UI_HIDDEN)
+        || (level == ComponentCallbacks2.TRIM_MEMORY_RUNNING_CRITICAL)) {
       trimToSize(getMaxSize() / 2);
     }
   }

library/test/src/test/java/com/bumptech/glide/load/engine/bitmap_recycle/LruBitmapPoolTest.java

@@ -14,6 +14,7 @@
 import static org.mockito.Mockito.when;
 
 import android.graphics.Bitmap;
+import android.os.Build;
 import java.util.ArrayDeque;
 import java.util.ArrayList;
 import java.util.Collections;
@@ -98,25 +99,32 @@ public void testEvictedBitmapsAreRecycled() {
     }
   }
 
+  @Config(sdk = Build.VERSION_CODES.KITKAT)
   @Test
-  public void testTrimMemoryUiHiddenOrLessRemovesHalfOfBitmaps() {
+  public void testTrimMemoryUiHiddenOrLessRemovesHalfOfBitmaps_preM() {
     testTrimMemory(MAX_SIZE, TRIM_MEMORY_UI_HIDDEN, MAX_SIZE / 2);
   }
 
+  @Config(sdk = Build.VERSION_CODES.M)
+  @Test
+  public void testTrimMemoryUiHiddenOrLessRemovesHalfOfBitmaps_postM() {
+    testTrimMemory(MAX_SIZE, TRIM_MEMORY_UI_HIDDEN, 0);
+  }
+
   @Test
   public void testTrimMemoryRunningCriticalRemovesHalfOfBitmaps() {
     testTrimMemory(MAX_SIZE, TRIM_MEMORY_RUNNING_CRITICAL, MAX_SIZE / 2);
   }
 
   @Test
-  public void testTrimMemoryUiHiddenOrLessRemovesNoBitmapsIfPoolLessThanHalfFull() {
-    testTrimMemory(MAX_SIZE / 2, TRIM_MEMORY_UI_HIDDEN, 0);
+  public void testTrimMemoryRunningCriticalOrLessRemovesNoBitmapsIfPoolLessThanHalfFull() {
+    testTrimMemory(MAX_SIZE / 2, TRIM_MEMORY_RUNNING_CRITICAL, MAX_SIZE / 2);
   }
 
   @Test
   public void testTrimMemoryBackgroundOrGreaterRemovesAllBitmaps() {
     for (int trimLevel : new int[] {TRIM_MEMORY_BACKGROUND, TRIM_MEMORY_COMPLETE}) {
-      testTrimMemory(MAX_SIZE, trimLevel, MAX_SIZE);
+      testTrimMemory(MAX_SIZE, trimLevel, 0);
     }
   }
 
@@ -161,7 +169,7 @@ private void testTrimMemory(int fillSize, int trimLevel, int expectedSize) {
     LruBitmapPool pool = new LruBitmapPool(MAX_SIZE, strategy, ALLOWED_CONFIGS);
     fillPool(pool, fillSize);
     pool.trimMemory(trimLevel);
-    assertEquals("Failed level=" + trimLevel, expectedSize, strategy.numRemoves);
+    assertEquals("Failed level=" + trimLevel, expectedSize, strategy.bitmaps.size());
   }
 
   @Test