Add input dependencies to .img targets

They should have build/tools/releasetools/*.py as their
prerequisites.

Bug: 27954979
Change-Id: I51595fc91caaad38be3e47befb5df7ac2683bf14
diff --git a/core/Makefile b/core/Makefile
index c0294a6..6fb2458 100644
--- a/core/Makefile
+++ b/core/Makefile
@@ -1161,7 +1161,7 @@
 FULL_SYSTEMIMAGE_DEPS += $(BVBTOOL)
 endif
 
-$(BUILT_SYSTEMIMAGE): $(FULL_SYSTEMIMAGE_DEPS) $(INSTALLED_FILES_FILE)
+$(BUILT_SYSTEMIMAGE): $(FULL_SYSTEMIMAGE_DEPS) $(INSTALLED_FILES_FILE) $(BUILD_IMAGE_SRCS)
 	$(call build-systemimage-target,$@)
 
 INSTALLED_SYSTEMIMAGE := $(PRODUCT_OUT)/system.img
@@ -1375,7 +1375,8 @@
 # We just build this directly to the install location.
 INSTALLED_USERDATAIMAGE_TARGET := $(BUILT_USERDATAIMAGE_TARGET)
 $(INSTALLED_USERDATAIMAGE_TARGET): $(INTERNAL_USERIMAGES_DEPS) \
-                                   $(INTERNAL_USERDATAIMAGE_FILES)
+                                   $(INTERNAL_USERDATAIMAGE_FILES) \
+                                   $(BUILD_IMAGE_SRCS)
 	$(build-userdataimage-target)
 
 .PHONY: userdataimage-nodeps
@@ -1459,7 +1460,7 @@
 
 # We just build this directly to the install location.
 INSTALLED_CACHEIMAGE_TARGET := $(BUILT_CACHEIMAGE_TARGET)
-$(INSTALLED_CACHEIMAGE_TARGET): $(INTERNAL_USERIMAGES_DEPS) $(INTERNAL_CACHEIMAGE_FILES)
+$(INSTALLED_CACHEIMAGE_TARGET): $(INTERNAL_USERIMAGES_DEPS) $(INTERNAL_CACHEIMAGE_FILES) $(BUILD_IMAGE_SRCS)
 	$(build-cacheimage-target)
 
 .PHONY: cacheimage-nodeps
@@ -1504,7 +1505,7 @@
 
 # We just build this directly to the install location.
 INSTALLED_VENDORIMAGE_TARGET := $(BUILT_VENDORIMAGE_TARGET)
-$(INSTALLED_VENDORIMAGE_TARGET): $(INTERNAL_USERIMAGES_DEPS) $(INTERNAL_VENDORIMAGE_FILES) $(INSTALLED_FILES_FILE_VENDOR)
+$(INSTALLED_VENDORIMAGE_TARGET): $(INTERNAL_USERIMAGES_DEPS) $(INTERNAL_VENDORIMAGE_FILES) $(INSTALLED_FILES_FILE_VENDOR) $(BUILD_IMAGE_SRCS)
 	$(build-vendorimage-target)
 
 .PHONY: vendorimage-nodeps
diff --git a/core/config.mk b/core/config.mk
index e63a135..563bce4 100644
--- a/core/config.mk
+++ b/core/config.mk
@@ -563,6 +563,7 @@
 PROGUARD := external/proguard/bin/proguard.sh
 JAVATAGS := build/tools/java-event-log-tags.py
 MERGETAGS := build/tools/merge-event-log-tags.py
+BUILD_IMAGE_SRCS := $(wildcard build/tools/releasetools/*.py)
 APPEND2SIMG := $(HOST_OUT_EXECUTABLES)/append2simg
 VERITY_SIGNER := $(HOST_OUT_EXECUTABLES)/verity_signer
 BUILD_VERITY_TREE := $(HOST_OUT_EXECUTABLES)/build_verity_tree