Add LOCAL_GENERATED_SOURCES to androidmk

Added the LOCAL_GENERATED_SOURCES support to the androidmk tool.

Bug: 216527541
Test: TreeHugger
Change-Id: I05b7aa4be6b50e405ec8ec15765d375a4626cc48

androidmk/androidmk/android.go

@@ -191,6 +191,7 @@ func init() {
 			// will be removed later by byfix
 			// TODO: does this property matter in the license module?
 			"LOCAL_LICENSE_CONDITIONS": "android_license_conditions",
+			"LOCAL_GENERATED_SOURCES":  "generated_sources",
 		})
 
 	addStandardProperties(bpparser.BoolType,

androidmk/androidmk/androidmk_test.go

@@ -1618,6 +1618,31 @@ android_app {
 		name: "foo",
 
 }
+`,
+	},
+	{
+		desc: "LOCAL_GENERATED_SOURCES",
+		in: `
+include $(CLEAR_VARS)
+LOCAL_MODULE := foo
+LOCAL_SRC_FILES := src1, src2, src3
+LOCAL_GENERATED_SOURCES := gen_src1, gen_src2, gen_src3
+include $(BUILD_PACKAGE)
+		`,
+		expected: `
+android_app {
+	name: "foo",
+	srcs: [
+		"src1,",
+		"src2,",
+		"src3",
+	],
+	generated_sources: [
+		"gen_src1,",
+		"gen_src2,",
+		"gen_src3",
+	],
+}
 `,
 	},
 }