Replace raw value for constant error value in string operations

Currently Find() and other methods that return a FX_STRSIZE return -1
to indicate error/failure. This means that there is a lot of magic
numbers and magic checks floating around. The standard library for
similar operations uses a npos constant. This CL implements
FX_STRNPOS, and replaces usages of magic number checking. It also does
some type cleanup along the way where it was obvious that FX_STRSIZE
should be being used.

Removing the magic numbers should make eventually changing FX_STRSIZE
to be unsigned easier in the future.

BUG=pdfium:828

Change-Id: I67e481e44cf2f75a1698afa8fbee4f375a74c490
Reviewed-on: https://pdfium-review.googlesource.com/9651
Commit-Queue: Ryan Harrison <rharrison@chromium.org>
Reviewed-by: Tom Sepez <tsepez@chromium.org>

1 files changed, 2 insertions, 2 deletions

diff --git a/core/fxcrt/xml/cfx_xmlelement.cpp b/core/fxcrt/xml/cfx_xmlelement.cpp
index 8c2442e765..75bf9ee593 100644
--- a/core/fxcrt/xml/cfx_xmlelement.cpp
+++ b/core/fxcrt/xml/cfx_xmlelement.cpp
@@ -43,14 +43,14 @@ std::unique_ptr<CFX_XMLNode> CFX_XMLElement::Clone() {
 
 CFX_WideString CFX_XMLElement::GetLocalTagName() const {
   FX_STRSIZE iFind = GetName().Find(L':', 0);
-  if (iFind < 0)
+  if (iFind == FX_STRNPOS)
     return GetName();
   return GetName().Right(GetName().GetLength() - iFind - 1);
 }
 
 CFX_WideString CFX_XMLElement::GetNamespacePrefix() const {
   FX_STRSIZE iFind = GetName().Find(L':', 0);
-  if (iFind < 0)
+  if (iFind == FX_STRNPOS)
     return CFX_WideString();
   return GetName().Left(iFind);
 }