Add HINT_FROM_SOONG option for ninja weight list

If this option is set, Soong generates ninja weight list including
modules in HugeModulesList in allowlists.go

Test: m --ninja_weight_source=soong
Bug: 273282046
Change-Id: Id92b7f9f9e8152c1c46ae071c5821a479cf47bce
diff --git a/ui/build/ninja.go b/ui/build/ninja.go
index cd528ba..5d56531 100644
--- a/ui/build/ninja.go
+++ b/ui/build/ninja.go
@@ -136,7 +136,9 @@
 		// pass empty weight list means ninja considers every tasks's weight as 1(default value).
 		cmd.Args = append(cmd.Args, "-o", "usesweightlist=/dev/null")
 	case EXTERNAL_FILE:
-		// The weight list is already copied.
+		fallthrough
+	case HINT_FROM_SOONG:
+		// The weight list is already copied/generated.
 		ninjaWeightListPath := filepath.Join(config.OutDir(), ninjaWeightListFileName)
 		cmd.Args = append(cmd.Args, "-o", "usesweightlist="+ninjaWeightListPath)
 	}