Use relative path instead of base for python proto

We encountered a duplicate sources bug in python proto generation
because we're only using the base name. This CL makes it use the
entire path to avoid this.

Fixes: 295333879
Test: Presubmits
Change-Id: I4ab821508cd5979bd595e327c1ccd3d68110fba6
diff --git a/python/proto.go b/python/proto.go
index 400e72c..ad2b786 100644
--- a/python/proto.go
+++ b/python/proto.go
@@ -19,7 +19,8 @@
 )
 
 func genProto(ctx android.ModuleContext, protoFile android.Path, flags android.ProtoFlags) android.Path {
-	srcsZipFile := android.PathForModuleGen(ctx, protoFile.Base()+".srcszip")
+	// Using protoFile.Base() would generate duplicate source errors in some cases, so we use Rel() instead
+	srcsZipFile := android.PathForModuleGen(ctx, protoFile.Rel()+".srcszip")
 
 	outDir := srcsZipFile.ReplaceExtension(ctx, "tmp")
 	depFile := srcsZipFile.ReplaceExtension(ctx, "srcszip.d")