XFA: merge patch from CL 733693003, getting rid of more casts

Getting rid of more (FX_LPCWSTR) casts and fixing two bugs revealed by this.

Since casts to FX_LPCWSTR have been shown to hide bugs I tried removing
more of them, targeting those places where a cast was used to force a
conversion from CFX_WideString to FX_LPCWSTR, replacing these casts with
calls to the newly added .c_str() function. This revealed two places
where the cast was hiding a bug -- where ->c_str() was required instead!

This removes ~33 FX_LPCWSTR casts and there are ~31 left, many of which
will go away in some future change.

Also includes this change:

Removing unnecessary casts from wchar_t* to wchar_t*, by various names.

Original patch from Bruce Dawson(brucedawson@chromium.org)

TBR=bo_xu@foxitsoftware.com, tsepez@chromium.org

Review URL: https://codereview.chromium.org/811593007

5 files changed, 6 insertions, 11 deletions

diff --git a/core/src/fxcrt/fx_basic_bstring.cpp b/core/src/fxcrt/fx_basic_bstring.cpp
index 60153fa45a..c54148d799 100644
--- a/core/src/fxcrt/fx_basic_bstring.cpp
+++ b/core/src/fxcrt/fx_basic_bstring.cpp
@@ -971,7 +971,7 @@ CFX_ByteString CFX_ByteString::FromUnicode(FX_LPCWSTR str, FX_STRSIZE len)
 }
 CFX_ByteString CFX_ByteString::FromUnicode(const CFX_WideString& str)
 {
-    return FromUnicode((FX_LPCWSTR)str, str.GetLength());
+    return FromUnicode(str.c_str(), str.GetLength());
 }
 void CFX_ByteString::ConvertFrom(const CFX_WideString& str, CFX_CharMap* pCharMap)
 {
diff --git a/core/src/fxcrt/fx_basic_buffer.cpp b/core/src/fxcrt/fx_basic_buffer.cpp
index 1734423253..b208142d92 100644
--- a/core/src/fxcrt/fx_basic_buffer.cpp
+++ b/core/src/fxcrt/fx_basic_buffer.cpp
@@ -192,7 +192,7 @@ CFX_WideTextBuf& CFX_WideTextBuf::operator << (FX_WSTR str)
 }
 CFX_WideTextBuf& CFX_WideTextBuf::operator << (const CFX_WideString &str)
 {
-    AppendBlock((FX_LPCWSTR)str, str.GetLength() * sizeof(FX_WCHAR));
+    AppendBlock(str.c_str(), str.GetLength() * sizeof(FX_WCHAR));
     return *this;
 }
 CFX_WideTextBuf& CFX_WideTextBuf::operator << (int i)
diff --git a/core/src/fxcrt/fx_extension.cpp b/core/src/fxcrt/fx_extension.cpp
index 330c675457..e74c52d4a8 100644
--- a/core/src/fxcrt/fx_extension.cpp
+++ b/core/src/fxcrt/fx_extension.cpp
@@ -158,7 +158,7 @@ FX_FLOAT FXSYS_strtof(FX_LPCSTR pcsStr, FX_INT32 iLength, FX_INT32 *pUsedLen)
         iLength = (FX_INT32)FXSYS_strlen(pcsStr);
     }
     CFX_WideString ws = CFX_WideString::FromLocal(pcsStr, iLength);
-    return FXSYS_wcstof((FX_LPCWSTR)ws, iLength, pUsedLen);
+    return FXSYS_wcstof(ws.c_str(), iLength, pUsedLen);
 }
 FX_FLOAT FXSYS_wcstof(FX_LPCWSTR pwsStr, FX_INT32 iLength, FX_INT32 *pUsedLen)
 {
diff --git a/core/src/fxcrt/fx_xml_parser.cpp b/core/src/fxcrt/fx_xml_parser.cpp
index ea471d4792..8049a5587e 100644
--- a/core/src/fxcrt/fx_xml_parser.cpp
+++ b/core/src/fxcrt/fx_xml_parser.cpp
@@ -670,18 +670,13 @@ FX_BOOL CXML_Element::GetAttrValue(FX_BSTR name, CFX_WideString& attribute) cons
 {
     CFX_ByteStringC bsSpace, bsName;
     FX_XML_SplitQualifiedName(name, bsSpace, bsName);
-    const CFX_WideString* pValue = m_AttrMap.Lookup(bsSpace, bsName);
-    if (pValue) {
-        attribute = CFX_WideString((FX_LPCWSTR)*pValue, pValue->GetLength());
-        return TRUE;
-    }
-    return FALSE;
+    return GetAttrValue(bsSpace, bsName, attribute);
 }
 FX_BOOL CXML_Element::GetAttrValue(FX_BSTR space, FX_BSTR name, CFX_WideString& attribute) const
 {
     const CFX_WideString* pValue = m_AttrMap.Lookup(space, name);
     if (pValue) {
-        attribute = CFX_WideString((FX_LPCWSTR)*pValue, pValue->GetLength());
+        attribute = *pValue;
         return TRUE;
     }
     return FALSE;
diff --git a/core/src/fxcrt/fxcrt_platforms.cpp b/core/src/fxcrt/fxcrt_platforms.cpp
index e14e362079..1c47ee6c9b 100644
--- a/core/src/fxcrt/fxcrt_platforms.cpp
+++ b/core/src/fxcrt/fxcrt_platforms.cpp
@@ -56,7 +56,7 @@ FX_BOOL CFXCRT_FileAccess_CRT::Open(FX_WSTR fileName, FX_DWORD dwMode)
     }
     CFX_WideString strMode;
     FXCRT_GetFileModeString(dwMode, strMode);
-    m_hFile = FXSYS_wfopen(fileName.GetPtr(), (FX_LPCWSTR)strMode);
+    m_hFile = FXSYS_wfopen(fileName.GetPtr(), strMode.c_str());
     return m_hFile != NULL;
 }
 void CFXCRT_FileAccess_CRT::Close()