Allow to pass in the use_ccache via go build.

Removes usage of go build tags in favor of passing in
configuration via -ldflags -X ...

BUG=chromium:773875
TEST=unit test

Change-Id: I4e8a58e1679b2858e9d4620d6b9c7a35ad08a6ee
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/toolchain-utils/+/1670987
Reviewed-by: George Burgess <gbiv@chromium.org>
Tested-by: Tobias Bosch <tbosch@google.com>
diff --git a/compiler_wrapper/compiler_wrapper.go b/compiler_wrapper/compiler_wrapper.go
index 72e1749..6034fb0 100644
--- a/compiler_wrapper/compiler_wrapper.go
+++ b/compiler_wrapper/compiler_wrapper.go
@@ -15,7 +15,7 @@
 	if err := checkUnsupportedFlags(wrapperCmd); err != nil {
 		return nil, err
 	}
-	builder, err := newCommandBuilder(env, wrapperCmd)
+	builder, err := newCommandBuilder(env, cfg, wrapperCmd)
 	if err != nil {
 		return nil, err
 	}