Add sdk_version property to imported jars

Test: m checkbuild
Change-Id: I83dd6ad157c7a5918747ce8c9be05c1e1e22d710

java/androidmk.go

@@ -76,6 +76,7 @@ func (prebuilt *Import) AndroidMk() android.AndroidMkData {
 			func(w io.Writer, outputFile android.Path) {
 				fmt.Fprintln(w, "LOCAL_UNINSTALLABLE_MODULE := true")
 				fmt.Fprintln(w, "LOCAL_SOONG_HEADER_JAR :=", prebuilt.combinedClasspathFile.String())
+				fmt.Fprintln(w, "LOCAL_SDK_VERSION :=", prebuilt.properties.Sdk_version)
 			},
 		},
 	}

java/java.go

@@ -913,6 +913,8 @@ func BinaryHostFactory() android.Module {
 
 type ImportProperties struct {
 	Jars []string
+
+	Sdk_version string
 }
 
 type Import struct {