Don't strip for eng builds.

bug: 72150787
Test: m
Change-Id: Ifdd403dfecb440e32c4d0c00a7543820b2098359
diff --git a/core/dex_preopt.mk b/core/dex_preopt.mk
index 0dcb07f..83c4a95 100644
--- a/core/dex_preopt.mk
+++ b/core/dex_preopt.mk
@@ -35,12 +35,14 @@
 # Conditional to building on linux, as dex2oat currently does not work on darwin.
 ifeq ($(HOST_OS),linux)
   WITH_DEXPREOPT ?= true
-# For an eng build only pre-opt the boot image and system server. This gives reasonable performance
-# and still allows a simple workflow: building in frameworks/base and syncing.
   ifeq (eng,$(TARGET_BUILD_VARIANT))
+    # Don't strip for quick development turnarounds.
+    DEX_PREOPT_DEFAULT := nostripping
+    # For an eng build only pre-opt the boot image and system server. This gives reasonable performance
+    # and still allows a simple workflow: building in frameworks/base and syncing.
     WITH_DEXPREOPT_BOOT_IMG_AND_SYSTEM_SERVER_ONLY ?= true
   endif
-# Add mini-debug-info to the boot classpath unless explicitly asked not to.
+  # Add mini-debug-info to the boot classpath unless explicitly asked not to.
   ifneq (false,$(WITH_DEXPREOPT_DEBUG_INFO))
     PRODUCT_DEX_PREOPT_BOOT_FLAGS += --generate-mini-debug-info
   endif