bp2build/queryview: codegen control sequences literally.

See b/184026959 for an instance where a genrule's cmd contains \n, and
the codegenerator generates an applied newline. It should be the
original newline control sequence literal.

Test: TH, bp2build unit test
Fixes: 184026959

Change-Id: Idb99ea87c75dfa4cb3ae679f98d8f61cb5a5ab09

bp2build/build_conversion_test.go

@@ -239,6 +239,22 @@ func TestGenerateBazelTargetModules(t *testing.T) {
         "b",
     ],
     string_prop = "a",
+)`,
+		},
+		{
+			bp: `custom {
+	name: "control_characters",
+    string_list_prop: ["\t", "\n"],
+    string_prop: "a\t\n\r",
+    bazel_module: { bp2build_available: true },
+}`,
+			expectedBazelTarget: `custom(
+    name = "control_characters",
+    string_list_prop = [
+        "\t",
+        "\n",
+    ],
+    string_prop = "a\t\n\r",
 )`,
 		},
 	}