Revert "Enable blurs by default"

This reverts commit 08593ccd9508f893ff39086ec044404dcaf42af4.

Reason for revert: There are a few performance issues we need to address on this device before merging this CL.

Change-Id: I0540ebb4a799a83e1054eda2cb5739ecf930b119
Bug: 154033053
diff --git a/device-common.mk b/device-common.mk
index 859f6c1..9fdf29d 100644
--- a/device-common.mk
+++ b/device-common.mk
@@ -913,7 +913,8 @@
 
 # Enable blurs, hidden under dev option
 PRODUCT_PRODUCT_PROPERTIES += \
-    ro.surface_flinger.supports_background_blur=1
+    ro.surface_flinger.supports_background_blur=1 \
+    persist.sys.sf.disable_blurs=1
 
 $(call inherit-product, $(SRC_TARGET_DIR)/product/virtual_ab_ota.mk)