Convert string Find methods to return an Optional

The Find and ReverseFind methods for WideString, WideStringC,
ByteString, and ByteStringC have been converted from returning a raw
FX_STRSIZE, to returning Optional<FX_STRSIZE>, so that success/failure
can be indicated without using FX_STRNPOS.

This allows for removing FX_STRNPOS and by association makes the
conversion of FX_STRSIZE to size_t easier, since it forces checking
the return value of Find to be explictly done as well as taking the
error value out of the range of FX_STRSIZE.

New Contains methods have been added for cases where the success or
failure is all the call site to Find cared about, and the actual
position was ignored.

BUG=pdfium:828


Change-Id: Id827e508c8660affa68cc08a13d96121369364b7
Reviewed-on: https://pdfium-review.googlesource.com/11350
Commit-Queue: Ryan Harrison <rharrison@chromium.org>
Reviewed-by: dsinclair <dsinclair@chromium.org>

1 files changed, 1 insertions, 1 deletions

diff --git a/fxbarcode/oned/BC_OneDimWriter.cpp b/fxbarcode/oned/BC_OneDimWriter.cpp
index 29c360921f..69c031608c 100644
--- a/fxbarcode/oned/BC_OneDimWriter.cpp
+++ b/fxbarcode/oned/BC_OneDimWriter.cpp
@@ -279,7 +279,7 @@ bool CBC_OneDimWriter::RenderDeviceResult(CFX_RenderDevice* device,
                      FXFILL_WINDING);
   }
 
-  return m_locTextLoc == BC_TEXT_LOC_NONE || contents.Find(' ') == FX_STRNPOS ||
+  return m_locTextLoc == BC_TEXT_LOC_NONE || !contents.Contains(' ') ||
          ShowChars(contents, device, matrix, m_barWidth, m_multiple);
 }