Allow remote execution of link actions.

This CL adds a remoteexec package that allows adding a configurable RBE
prefix to the template.

Change-Id: I6b4ea773f6bae5706415a1830f822db7decca92f
Test: built aosp crosshatch userdebug with and without RBE_CXX_LINKS.
Merged-In: Ica920c3d7f79f2996210b9cbd448126451c1707c
Bug: b/154820732
diff --git a/ui/build/dumpvars.go b/ui/build/dumpvars.go
index ce8f968..a3234e3 100644
--- a/ui/build/dumpvars.go
+++ b/ui/build/dumpvars.go
@@ -190,6 +190,7 @@
 		// compiler wrappers set up by make
 		"CC_WRAPPER",
 		"CXX_WRAPPER",
+		"RBE_WRAPPER",
 		"JAVAC_WRAPPER",
 		"R8_WRAPPER",
 		"D8_WRAPPER",