Store WideString, not raw pointer, in FX_TXTRUN

Storing raw pointers in structs is a questionable idea, given
that we've got string classes to auto-manage lifetimes of the
underlying storage.

Also, return FX_TXTRUN while we're at it, since we count on RVO
removing copies nowadays.

BUG=pdfium:480

Review URL: https://codereview.chromium.org/1900743004

2 files changed, 18 insertions, 20 deletions

diff --git a/xfa/fgas/layout/fgas_textbreak.cpp b/xfa/fgas/layout/fgas_textbreak.cpp
index 0face90abd..f8cfcd0066 100644
--- a/xfa/fgas/layout/fgas_textbreak.cpp
+++ b/xfa/fgas/layout/fgas_textbreak.cpp
@@ -1174,7 +1174,7 @@ int32_t CFX_TxtBreak::GetDisplayPos(const FX_TXTRUN* pTxtRun,
   }
   IFX_TxtAccess* pAccess = pTxtRun->pAccess;
   void* pIdentity = pTxtRun->pIdentity;
-  const FX_WCHAR* pStr = pTxtRun->pStr;
+  const FX_WCHAR* pStr = pTxtRun->wsStr.c_str();
   int32_t* pWidths = pTxtRun->pWidths;
   int32_t iLength = pTxtRun->iLength - 1;
   IFX_Font* pFont = pTxtRun->pFont;
@@ -1554,7 +1554,7 @@ int32_t CFX_TxtBreak::GetCharRects(const FX_TXTRUN* pTxtRun,
   }
   IFX_TxtAccess* pAccess = pTxtRun->pAccess;
   void* pIdentity = pTxtRun->pIdentity;
-  const FX_WCHAR* pStr = pTxtRun->pStr;
+  const FX_WCHAR* pStr = pTxtRun->wsStr.c_str();
   int32_t* pWidths = pTxtRun->pWidths;
   int32_t iLength = pTxtRun->iLength;
   CFX_RectF rect(*pTxtRun->pRect);
diff --git a/xfa/fgas/layout/fgas_textbreak.h b/xfa/fgas/layout/fgas_textbreak.h
index b83f2604c8..af6d52163f 100644
--- a/xfa/fgas/layout/fgas_textbreak.h
+++ b/xfa/fgas/layout/fgas_textbreak.h
@@ -79,27 +79,25 @@ class IFX_TxtAccess {
 };
 
 struct FX_TXTRUN {
-  FX_TXTRUN() {
-    pAccess = NULL;
-    pIdentity = NULL;
-    pStr = NULL;
-    pWidths = NULL;
-    iLength = 0;
-    pFont = NULL;
-    fFontSize = 12;
-    dwStyles = 0;
-    iHorizontalScale = 100;
-    iVerticalScale = 100;
-    iCharRotation = 0;
-    dwCharStyles = 0;
-    pRect = NULL;
-    wLineBreakChar = L'\n';
-    bSkipSpace = TRUE;
-  }
+  FX_TXTRUN()
+      : pAccess(nullptr),
+        pIdentity(nullptr),
+        pWidths(nullptr),
+        iLength(0),
+        pFont(nullptr),
+        fFontSize(12),
+        dwStyles(0),
+        iHorizontalScale(100),
+        iVerticalScale(100),
+        iCharRotation(0),
+        dwCharStyles(0),
+        pRect(nullptr),
+        wLineBreakChar(L'\n'),
+        bSkipSpace(TRUE) {}
 
   IFX_TxtAccess* pAccess;
   void* pIdentity;
-  const FX_WCHAR* pStr;
+  CFX_WideString wsStr;
   int32_t* pWidths;
   int32_t iLength;
   IFX_Font* pFont;