Remove disable_blurs sysprop from SF

The disable_blurs sysprop is now redundant, because the window-level
blurs are disabled in the system server. If blurs are supported on the
device, SurfaceFlinger should render them.

Bug: 185580298
Test: m && flash
Change-Id: If4503a26416d3586e85a14c9e3c0052173235e6f
diff --git a/services/surfaceflinger/SurfaceFlinger.cpp b/services/surfaceflinger/SurfaceFlinger.cpp
index 881ee5b..d23553f 100644
--- a/services/surfaceflinger/SurfaceFlinger.cpp
+++ b/services/surfaceflinger/SurfaceFlinger.cpp
@@ -789,11 +789,6 @@
 
     property_get("persist.sys.sf.color_mode", value, "0");
     mForceColorMode = static_cast<ColorMode>(atoi(value));
-
-    property_get("persist.sys.sf.disable_blurs", value, "0");
-    bool disableBlurs = atoi(value);
-    mDisableBlurs = disableBlurs;
-    ALOGI_IF(disableBlurs, "Disabling blur effects, user preference.");
 }
 
 void SurfaceFlinger::startBootAnim() {
@@ -3953,7 +3948,7 @@
         if (layer->setCornerRadius(s.cornerRadius))
             flags |= eTraversalNeeded;
     }
-    if (what & layer_state_t::eBackgroundBlurRadiusChanged && !mDisableBlurs && mSupportsBlur) {
+    if (what & layer_state_t::eBackgroundBlurRadiusChanged && mSupportsBlur) {
         if (layer->setBackgroundBlurRadius(s.backgroundBlurRadius)) flags |= eTraversalNeeded;
     }
     if (what & layer_state_t::eBlurRegionsChanged) {