Merge fCurrIncrementalCodec and fCurrScanlineCodec usage into single 
variable

This patch merges fCurrIncrementalCodec and fCurrScanlineCodec usage
into single variable for SkIcoCodec.

Bug: skia: None
Change-Id: I6629f04fc27b8792c4cb1e6f494f8df7006c6b21
Reviewed-on: https://skia-review.googlesource.com/50520
Reviewed-by: Leon Scroggins <scroggo@google.com>
Commit-Queue: Leon Scroggins <scroggo@google.com>
2 files changed