Revert^3 "add rust_toolchain_rustc_prebuilt module type"

9333ac12499f1c56cb74618699c5bce3799c1f19

Change-Id: Ic7f064806553a0cfbc286136a764b5ea3898d06c
diff --git a/android/prebuilt_build_tool.go b/android/prebuilt_build_tool.go
index 17b3230..aeae20f 100644
--- a/android/prebuilt_build_tool.go
+++ b/android/prebuilt_build_tool.go
@@ -17,7 +17,7 @@
 import "path/filepath"
 
 func init() {
-	RegisterModuleType("prebuilt_build_tool", NewPrebuiltBuildTool)
+	RegisterModuleType("prebuilt_build_tool", prebuiltBuildToolFactory)
 }
 
 type prebuiltBuildToolProperties struct {
@@ -101,6 +101,10 @@
 
 // prebuilt_build_tool is to declare prebuilts to be used during the build, particularly for use
 // in genrules with the "tools" property.
+func prebuiltBuildToolFactory() Module {
+	return NewPrebuiltBuildTool()
+}
+
 func NewPrebuiltBuildTool() Module {
 	module := &prebuiltBuildTool{}
 	module.AddProperties(&module.properties)