mojo/shared: use CURDIR instead of PWD, because make -C does not update
pwd.

Change-Id: Iff458d249a812f960634685bc118cf51ee9aa11d
diff --git a/mojo.mk b/mojo.mk
index 821f911..114479e 100644
--- a/mojo.mk
+++ b/mojo.mk
@@ -30,7 +30,7 @@
 MOJO_SHARED_LIB := $(shell jiri v23-profile env --profiles=$(MOJO_PROFILE) --target=$(TARGET) MOJO_SYSTEM_THUNKS=)
 MOJO_SHELL := $(shell jiri v23-profile env --profiles=$(MOJO_PROFILE) --target=$(TARGET) MOJO_SHELL=)
 
-export GOPATH := $(PWD)/go:$(PWD)/gen/go
+export GOPATH := $(GOPATH):$(CURDIR)/go:$(CURDIR)/gen/go
 
 # NOTE(nlacasse): Running Go Mojo services requires passing the
 # --enable-multiprocess flag to mojo_shell.  This is because the Go runtime is
@@ -63,7 +63,7 @@
 endef
 
 define MOJO_RUN
-	$(MOJO_DEVTOOLS)/mojo_run --config-file $(PWD)/mojoconfig --shell-path $(MOJO_SHELL) $(MOJO_SHELL_FLAGS) $(MOJO_ANDROID_FLAGS) $1
+	$(MOJO_DEVTOOLS)/mojo_run --config-file $(CURDIR)/mojoconfig --shell-path $(MOJO_SHELL) $(MOJO_SHELL_FLAGS) $(MOJO_ANDROID_FLAGS) $1
 endef
 
 .PHONY: mojo-env-check