Work around bug with abspath on windows.
On windows, abspath will mangle a path that is already absolute instead
of leaving it alone. Use the functions built into the NDK to
only create an absolute path if it is not already absolute.
diff --git a/third_party/Android.mk b/third_party/Android.mk
index eb78abd..c527838 100644
--- a/third_party/Android.mk
+++ b/third_party/Android.mk
@@ -59,7 +59,7 @@
include $(CLEAR_VARS)
-GLSLANG_OUT_PATH=$(abspath $(TARGET_OUT))
+GLSLANG_OUT_PATH=$(if $(call host-path-is-absolute,$(TARGET_OUT)),$(TARGET_OUT),$(abspath $(TARGET_OUT)))
LOCAL_MODULE:=glslang
LOCAL_CXXFLAGS:=-std=c++11 -fno-exceptions -fno-rtti $(GLSLANG_OS_FLAGS)
@@ -106,7 +106,7 @@
SPVTOOLS_LOCAL_PATH := $(THIRD_PARTY_PATH)/spirv-tools
LOCAL_PATH := $(SPVTOOLS_LOCAL_PATH)
-SPVTOOLS_OUT_PATH=$(abspath $(TARGET_OUT))
+SPVTOOLS_OUT_PATH=$(if $(call host-path-is-absolute,$(TARGET_OUT)),$(TARGET_OUT),$(abspath $(TARGET_OUT)))
SPVHEADERS_LOCAL_PATH := $(THIRD_PARTY_PATH)/spirv-tools/external/spirv-headers
# Locations of grammar files.
