Temporarily add method to get java binary tool

cc binaries are moving from out/soong/host/linux-x86/bin to
out/host/linux-86/bin first, to be followed by java binaries.
Temporarily add a method that gets the java binary path while
it is different from the cc binary path.

Bug: 204136549
Test: m checkbuild
Change-Id: I04a7e741436da6be68078f23d074870413a5bb5e

android/config.go

@@ -585,6 +585,11 @@ func (c *config) HostJavaToolPath(ctx PathContext, path string) Path {
 	return PathForOutput(ctx, "host", c.PrebuiltOS(), "framework", path)
 }
 
+func (c *config) HostJavaBinToolPath(ctx PathContext, tool string) Path {
+	path := pathForInstall(ctx, ctx.Config().BuildOS, ctx.Config().BuildArch, "bin", false, tool)
+	return path
+}
+
 // PrebuiltOS returns the name of the host OS used in prebuilts directories.
 func (c *config) PrebuiltOS() string {
 	switch runtime.GOOS {

android/package_ctx.go

@@ -177,6 +177,16 @@ func (p PackageContext) HostBinToolVariable(name, path string) blueprint.Variabl
 	})
 }
 
+// HostJavaBinToolVariable returns a Variable whose value is the path to a host java tool
+// in the bin directory for host java targets. It may only be called during a Go
+// package's initialization - either from the init() function or as part of a
+// package-scoped variable's initialization.
+func (p PackageContext) HostJavaBinToolVariable(name, path string) blueprint.Variable {
+	return p.VariableFunc(name, func(ctx PackageVarContext) string {
+		return ctx.Config().HostJavaBinToolPath(ctx, path).String()
+	})
+}
+
 // HostJNIToolVariable returns a Variable whose value is the path to a host tool
 // in the lib directory for host targets. It may only be called during a Go
 // package's initialization - either from the init() function or as part of a

java/config/config.go

@@ -124,8 +124,8 @@ func init() {
 	pctx.HostBinToolVariable("Zip2ZipCmd", "zip2zip")
 	pctx.HostBinToolVariable("ZipSyncCmd", "zipsync")
 	pctx.HostBinToolVariable("ApiCheckCmd", "apicheck")
-	pctx.HostBinToolVariable("D8Cmd", "d8")
+	pctx.HostJavaBinToolVariable("D8Cmd", "d8")
-	pctx.HostBinToolVariable("R8Cmd", "r8-compat-proguard")
+	pctx.HostJavaBinToolVariable("R8Cmd", "r8-compat-proguard")
 	pctx.HostBinToolVariable("HiddenAPICmd", "hiddenapi")
 	pctx.HostBinToolVariable("ExtractApksCmd", "extract_apks")
 	pctx.VariableFunc("TurbineJar", func(ctx android.PackageVarContext) string {