Reset frame state after UI_HIDDEN and minor cleanup.

PiperOrigin-RevId: 342767032

Author: sjudd

library/src/main/java/com/bumptech/glide/load/resource/bitmap/HardwareConfigState.java

@@ -126,12 +126,17 @@ public static HardwareConfigState getInstance() {
     }
   }
 
-  public synchronized void blockHardwareBitmaps() {
+  public boolean areHardwareBitmapsBlocked() {
+    Util.assertMainThread();
+    return !isHardwareConfigAllowedByAppState.get();
+  }
+
+  public void blockHardwareBitmaps() {
     Util.assertMainThread();
     isHardwareConfigAllowedByAppState.set(false);
   }
 
-  public synchronized void unblockHardwareBitmaps() {
+  public void unblockHardwareBitmaps() {
     Util.assertMainThread();
     isHardwareConfigAllowedByAppState.set(true);
   }

library/src/main/java/com/bumptech/glide/manager/FirstFrameAndAfterTrimMemoryWaiter.java

@@ -20,5 +20,7 @@ public void onTrimMemory(int level) {}
   public void onConfigurationChanged(@NonNull Configuration newConfig) {}
 
   @Override
-  public void onLowMemory() {}
+  public void onLowMemory() {
+    onTrimMemory(TRIM_MEMORY_UI_HIDDEN);
+  }
 }