Decouple SysUI blurs from cross window blur API

This way, enabling the API wouldn't necessarily enable blurs on sysui as
well.

Test: manual
Change-Id: If961d94d808bc9aacd8eb5de6a75e2cfabd6dcea
Bug: 192085653

packages/SystemUI/shared/src/com/android/systemui/shared/system/BlurUtils.java

@@ -19,6 +19,7 @@ package com.android.systemui.shared.system;
 import static android.view.CrossWindowBlurListeners.CROSS_WINDOW_BLUR_SUPPORTED;
 
 import android.app.ActivityManager;
+import android.os.SystemProperties;
 
 public abstract class BlurUtils {
 
@@ -28,6 +29,7 @@ public abstract class BlurUtils {
      * @return {@code true} when supported.
      */
     public static boolean supportsBlursOnWindows() {
-        return CROSS_WINDOW_BLUR_SUPPORTED && ActivityManager.isHighEndGfx();
+        return CROSS_WINDOW_BLUR_SUPPORTED && ActivityManager.isHighEndGfx()
+                && !SystemProperties.getBoolean("persist.sysui.disableBlur", false);
     }
 }

packages/SystemUI/src/com/android/systemui/statusbar/BlurUtils.kt

@@ -20,6 +20,7 @@ import android.view.CrossWindowBlurListeners.CROSS_WINDOW_BLUR_SUPPORTED
 
 import android.app.ActivityManager
 import android.content.res.Resources
+import android.os.SystemProperties
 import android.util.IndentingPrintWriter
 import android.util.MathUtils
 import android.view.CrossWindowBlurListeners
@@ -100,7 +101,8 @@ open class BlurUtils @Inject constructor(
      */
     open fun supportsBlursOnWindows(): Boolean {
         return CROSS_WINDOW_BLUR_SUPPORTED && ActivityManager.isHighEndGfx() &&
-                crossWindowBlurListeners.isCrossWindowBlurEnabled()
+                crossWindowBlurListeners.isCrossWindowBlurEnabled() &&
+                !SystemProperties.getBoolean("persist.sysui.disableBlur", false)
     }
 
     override fun dump(fd: FileDescriptor, pw: PrintWriter, args: Array<out String>) {