Allow .o files as srcs.

Test: m nothing
Test: TreeHugger
Bug: 134581881
Bug: 137267623

Change-Id: I26307dd1129e58878f0468da3b61c53f074bd674
diff --git a/cc/cc_test.go b/cc/cc_test.go
index c619b5a..99a88e9 100644
--- a/cc/cc_test.go
+++ b/cc/cc_test.go
@@ -2203,7 +2203,7 @@
 	ctx := testCc(t, `
 		cc_binary {
 			name: "static_test",
-			srcs: ["foo.c"],
+			srcs: ["foo.c", "baz.o"],
 			static_executable: true,
 		}`)