Revert "Return pdfium::span<wchar_t> from WideString::GetBuffer()."

This reverts commit 154e18f9a862975abecebe77b8f5fb418418d14c.

Reason for revert: Generate CL to merge to beta branch

Original change's description:
> Return pdfium::span<wchar_t> from WideString::GetBuffer().
> 
> Adds bounds checking "for free", but beware of span outliving
> a ReleaseBuffer() call.  Scoping as such avoids the possibility
> of using an invalid span (and it is flagged as a lifetime issue).
> 
> Change-Id: Ica63f4b1429823d0254ec6951aeaeb08160cb93c
> Reviewed-on: https://pdfium-review.googlesource.com/30310
> Reviewed-by: dsinclair <dsinclair@chromium.org>
> Commit-Queue: Tom Sepez <tsepez@chromium.org>

TBR=tsepez@chromium.org,dsinclair@chromium.org

# Not skipping CQ checks because original CL landed > 1 day ago.

Change-Id: Ie1ec9434215584a024538ca8edeb59dea555af48
Reviewed-on: https://pdfium-review.googlesource.com/30830
Reviewed-by: Tom Sepez <tsepez@chromium.org>
Reviewed-by: dsinclair <dsinclair@chromium.org>
Commit-Queue: Tom Sepez <tsepez@chromium.org>

1 files changed, 13 insertions, 15 deletions

diff --git a/xfa/fxfa/cxfa_textlayout.cpp b/xfa/fxfa/cxfa_textlayout.cpp
index 5359a340e5..e360c16dde 100644
--- a/xfa/fxfa/cxfa_textlayout.cpp
+++ b/xfa/fxfa/cxfa_textlayout.cpp
@@ -911,23 +911,21 @@ void CXFA_TextLayout::ProcessText(WideString& wsText) {
   if (iLen == 0)
     return;
 
+  wchar_t* psz = wsText.GetBuffer(iLen);
   int32_t iTrimLeft = 0;
-  {
-    // Span's lifetime must end before ReleaseBuffer() below.
-    pdfium::span<wchar_t> psz = wsText.GetBuffer(iLen);
-    wchar_t wPrev = 0;
-    for (int32_t i = 0; i < iLen; i++) {
-      wchar_t wch = psz[i];
-      if (wch < 0x20)
-        wch = 0x20;
-      if (wch == 0x20 && wPrev == 0x20)
-        continue;
-
-      wPrev = wch;
-      psz[iTrimLeft++] = wch;
-    }
+  wchar_t wch = 0, wPrev = 0;
+  for (int32_t i = 0; i < iLen; i++) {
+    wch = psz[i];
+    if (wch < 0x20)
+      wch = 0x20;
+    if (wch == 0x20 && wPrev == 0x20)
+      continue;
+
+    wPrev = wch;
+    psz[iTrimLeft++] = wch;
   }
-  wsText.ReleaseBuffer(iTrimLeft);
+  wsText.ReleaseBuffer(iLen);
+  wsText = wsText.Left(iTrimLeft);
 }
 
 void CXFA_TextLayout::EndBreak(CFX_BreakType dwStatus,