Tracking merge of dalvik-dev to master

git cherry-pick --no-commit  5fac8d8f7096d8a950acad1ad0a8b963cef72e03

git cherry-pick --no-commit  1a8210710b46a0796ff2f8e76b6beb3a54f89019

git cherry-pick --no-commit  4fe2ac9f7284b838393aec8f0f48caef2510fd46

git cherry-pick --no-commit  7beb710a8f976fc4cb1e8be780644386870c4975

Change-Id: Ib10348e5509c906c6b95fa4accd6a18900bfe748
diff --git a/core/definitions.mk b/core/definitions.mk
index 3b5c146..4b7b9a5 100644
--- a/core/definitions.mk
+++ b/core/definitions.mk
@@ -1349,6 +1349,12 @@
 xlint_unchecked := -Xlint:unchecked
 endif
 
+ifeq (true, $(ENABLE_INCREMENTALJAVAC))
+incremental_dex := --incremental
+else
+incremental_dex :=
+endif
+
 # emit-line, <word list>, <output file>
 define emit-line
    $(if $(1),echo -n '$(strip $(1)) ' >> $(2))
@@ -1507,6 +1513,7 @@
 $(hide) $(DX) \
     $(if $(findstring windows,$(HOST_OS)),,-JXms16M -JXmx1536M) \
     --dex --output=$@ \
+    $(incremental_dex) \
     $(if $(NO_OPTIMIZE_DX), \
         --no-optimize) \
     $(if $(GENERATE_DEX_DEBUG), \