Implement path-based enabling of code coverage.

Native coverage is enabled by setting NATIVE_COVERAGE to true
and specifying a list of paths in the COVERAGE_PATHS
environment variable. Files are exported to a zip file in the
target out directory.

Change-Id: I66a2ddd88e849bec1cc0cdae1b51fe18a007e2c3
diff --git a/core/envsetup.mk b/core/envsetup.mk
index a221fb9..39a754b 100644
--- a/core/envsetup.mk
+++ b/core/envsetup.mk
@@ -261,10 +261,12 @@
 HOST_OUT_JAVA_LIBRARIES := $(HOST_OUT)/framework
 HOST_OUT_SDK_ADDON := $(HOST_OUT)/sdk_addon
 HOST_OUT_NATIVE_TESTS := $(HOST_OUT)/nativetest64
+HOST_OUT_COVERAGE := $(HOST_OUT)/coverage
 
 HOST_CROSS_OUT_EXECUTABLES := $(HOST_CROSS_OUT)/bin
 HOST_CROSS_OUT_SHARED_LIBRARIES := $(HOST_CROSS_OUT)/lib
 HOST_CROSS_OUT_NATIVE_TESTS := $(HOST_CROSS_OUT)/nativetest
+HOST_CROSS_OUT_COVERAGE := $(HOST_CROSS_OUT)/coverage
 
 HOST_OUT_INTERMEDIATES := $(HOST_OUT)/obj
 HOST_OUT_HEADERS := $(HOST_OUT_INTERMEDIATES)/include
@@ -467,6 +469,7 @@
 TARGET_ROOT_OUT_UNSTRIPPED := $(TARGET_OUT_UNSTRIPPED)
 TARGET_ROOT_OUT_SBIN_UNSTRIPPED := $(TARGET_OUT_UNSTRIPPED)/sbin
 TARGET_ROOT_OUT_BIN_UNSTRIPPED := $(TARGET_OUT_UNSTRIPPED)/bin
+TARGET_OUT_COVERAGE := $(PRODUCT_OUT)/coverages
 
 TARGET_ROOT_OUT := $(PRODUCT_OUT)/$(TARGET_COPY_OUT_ROOT)
 TARGET_ROOT_OUT_BIN := $(TARGET_ROOT_OUT)/bin