Reland "Renamed SkSL "offset" to "line""

This reverts commit cc91452f0a65f261283615db9ed3d37b1c3acd15.

Change-Id: I7eff0ddeebef4ce298893f9b3ba410b09647e9a4
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/453138
Commit-Queue: Ethan Nicholas <ethannicholas@google.com>
Reviewed-by: John Stiles <johnstiles@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
diff --git a/src/sksl/codegen/SkSLMetalCodeGenerator.h b/src/sksl/codegen/SkSLMetalCodeGenerator.h
index e799dfb..1668e69 100644
--- a/src/sksl/codegen/SkSLMetalCodeGenerator.h
+++ b/src/sksl/codegen/SkSLMetalCodeGenerator.h
@@ -97,7 +97,7 @@
 
     void writeStructDefinitions();
 
-    void writeFields(const std::vector<Type::Field>& fields, int parentOffset,
+    void writeFields(const std::vector<Type::Field>& fields, int parentLine,
                      const InterfaceBlock* parentIntf = nullptr);
 
     int size(const Type* type, bool isPacked) const;