cc bazel handlers: use better interface checking

This is a far better approach for ensuring that bazel handlers implement
the BazelHandler interface, as it causes a compile error if they do not
implement the appropriate interface methods.

Test: Manually verified no change in ninja file
Change-Id: I63a4f8b57e3aedd4c0915c2fd2eb7029e9a993aa
diff --git a/cc/binary.go b/cc/binary.go
index 7b5591a..cfc54ff 100644
--- a/cc/binary.go
+++ b/cc/binary.go
@@ -563,11 +563,11 @@
 }
 
 type ccBinaryBazelHandler struct {
-	BazelHandler
-
 	module *Module
 }
 
+var _ BazelHandler = (*ccBinaryBazelHandler)(nil)
+
 func (handler *ccBinaryBazelHandler) QueueBazelCall(ctx android.BaseModuleContext, label string) {
 	bazelCtx := ctx.Config().BazelContext
 	bazelCtx.QueueBazelRequest(label, cquery.GetOutputFiles, android.GetConfigKey(ctx))