Revert^4 "allow Ninja variables in RuleBuilder API"

789a7e0883d5e142ff98898ac02797f106d38b9c

Change-Id: Iee1156adf0ad6e6d2ae7e22d90a447d4b564e59f
diff --git a/android/rule_builder.go b/android/rule_builder.go
index 777c1cf..97582db 100644
--- a/android/rule_builder.go
+++ b/android/rule_builder.go
@@ -474,13 +474,23 @@
 		Inputs(depFiles.Paths())
 }
 
+// BuildWithNinjaVars adds the built command line to the build graph, with dependencies on Inputs and Tools, and output files for
+// Outputs. This function will not escape Ninja variables, so it may be used to write sandbox manifests using Ninja variables.
+func (r *RuleBuilder) BuildWithUnescapedNinjaVars(name string, desc string) {
+	r.build(name, desc, false)
+}
+
 // Build adds the built command line to the build graph, with dependencies on Inputs and Tools, and output files for
 // Outputs.
 func (r *RuleBuilder) Build(name string, desc string) {
+	r.build(name, desc, true)
+}
+
+func (r *RuleBuilder) build(name string, desc string, ninjaEscapeCommandString bool) {
 	name = ninjaNameEscape(name)
 
 	if len(r.missingDeps) > 0 {
-		r.ctx.Build(pctx, BuildParams{
+		r.ctx.Build(r.pctx, BuildParams{
 			Rule:        ErrorRule,
 			Outputs:     r.Outputs(),
 			Description: desc,
@@ -619,12 +629,35 @@
 				name, r.sboxManifestPath.String(), r.outDir.String())
 		}
 
-		// Create a rule to write the manifest as a the textproto.
+		// Create a rule to write the manifest as textproto.
 		pbText, err := prototext.Marshal(&manifest)
 		if err != nil {
 			ReportPathErrorf(r.ctx, "sbox manifest failed to marshal: %q", err)
 		}
-		WriteFileRule(r.ctx, r.sboxManifestPath, string(pbText))
+		if ninjaEscapeCommandString {
+			WriteFileRule(r.ctx, r.sboxManifestPath, string(pbText))
+		} else {
+			// We need  to have a rule to write files that is
+			// defined on the RuleBuilder's pctx in order to
+			// write Ninja variables in the string.
+			// The WriteFileRule function above rule can only write
+			// raw strings because it is defined on the android
+			// package's pctx, and it can't access variables defined
+			// in another context.
+			r.ctx.Build(r.pctx, BuildParams{
+				Rule: r.ctx.Rule(r.pctx, "unescapedWriteFile", blueprint.RuleParams{
+					Command:        `rm -rf ${out} && cat ${out}.rsp > ${out}`,
+					Rspfile:        "${out}.rsp",
+					RspfileContent: "${content}",
+					Description:    "write file",
+				}, "content"),
+				Output:      r.sboxManifestPath,
+				Description: "write sbox manifest " + r.sboxManifestPath.Base(),
+				Args: map[string]string{
+					"content": string(pbText),
+				},
+			})
+		}
 
 		// Generate a new string to use as the command line of the sbox rule.  This uses
 		// a RuleBuilderCommand as a convenience method of building the command line, then
@@ -724,7 +757,7 @@
 	}
 
 	r.ctx.Build(r.pctx, BuildParams{
-		Rule: r.ctx.Rule(pctx, name, blueprint.RuleParams{
+		Rule: r.ctx.Rule(r.pctx, name, blueprint.RuleParams{
 			Command:        proptools.NinjaEscape(commandString),
 			CommandDeps:    proptools.NinjaEscapeList(tools.Strings()),
 			Restat:         r.restat,