Rename Left() and Right() in {Byte,Wide}String{,View} classes

Rename to First() and Last().

Bug: pdfium:1406
Change-Id: I786313c4ea044c9e27e532d9d25ba6c26f9228f4
Reviewed-on: https://pdfium-review.googlesource.com/c/pdfium/+/65613
Auto-Submit: Daniel Hosseinian <dhoss@chromium.org>
Reviewed-by: Lei Zhang <thestig@chromium.org>
Commit-Queue: Lei Zhang <thestig@chromium.org>
diff --git a/fxjs/cjs_util.cpp b/fxjs/cjs_util.cpp
index 37d3932..1f95c31 100644
--- a/fxjs/cjs_util.cpp
+++ b/fxjs/cjs_util.cpp
@@ -112,7 +112,7 @@
       Optional<size_t> offset_end = unsafe_fmt_string.Find(L"%", offset + 1);
       if (!offset_end.has_value()) {
         unsafe_conversion_specifiers.push_back(
-            unsafe_fmt_string.Right(unsafe_fmt_string.GetLength() - offset));
+            unsafe_fmt_string.Last(unsafe_fmt_string.GetLength() - offset));
         break;
       }
 
@@ -154,7 +154,7 @@
   DCHECK_EQ(L'S', result[0]);
   auto result_view = result.AsStringView();
   return CJS_Result::Success(
-      pRuntime->NewString(result_view.Right(result_view.GetLength() - 1)));
+      pRuntime->NewString(result_view.Last(result_view.GetLength() - 1)));
 }
 
 CJS_Result CJS_Util::printd(CJS_Runtime* pRuntime,