Convert string class names

Automated using git grep & sed.
Replace StringC classes with StringView classes.
Remove the CFX_ prefix and put string classes in fxcrt namespace.
Change AsStringC() to AsStringView().
Rename tests from TEST(fxcrt, *String*Foo) to TEST(*String*,
Foo).
Couple of tests needed to have their names regularlized.

BUG=pdfium:894

Change-Id: I7ca038685c8d803795f3ed02545124f7a224c83d
Reviewed-on: https://pdfium-review.googlesource.com/14151
Reviewed-by: Tom Sepez <tsepez@chromium.org>
Commit-Queue: Ryan Harrison <rharrison@chromium.org>
diff --git a/fxbarcode/cbc_code39.cpp b/fxbarcode/cbc_code39.cpp
index a46af14..9715c25 100644
--- a/fxbarcode/cbc_code39.cpp
+++ b/fxbarcode/cbc_code39.cpp
@@ -31,7 +31,7 @@
 
 CBC_Code39::~CBC_Code39() {}
 
-bool CBC_Code39::Encode(const CFX_WideStringC& contents) {
+bool CBC_Code39::Encode(const WideStringView& contents) {
   if (contents.IsEmpty())
     return false;
 
@@ -39,25 +39,25 @@
   int32_t outWidth = 0;
   int32_t outHeight = 0;
   auto* pWriter = GetOnedCode39Writer();
-  CFX_WideString filtercontents = pWriter->FilterContents(contents);
-  CFX_WideString renderContents = pWriter->RenderTextContents(contents);
+  WideString filtercontents = pWriter->FilterContents(contents);
+  WideString renderContents = pWriter->RenderTextContents(contents);
   m_renderContents = renderContents;
-  CFX_ByteString byteString = filtercontents.UTF8Encode();
+  ByteString byteString = filtercontents.UTF8Encode();
   std::unique_ptr<uint8_t, FxFreeDeleter> data(
       pWriter->Encode(byteString, format, outWidth, outHeight));
   if (!data)
     return false;
-  return pWriter->RenderResult(renderContents.AsStringC(), data.get(),
+  return pWriter->RenderResult(renderContents.AsStringView(), data.get(),
                                outWidth);
 }
 
 bool CBC_Code39::RenderDevice(CFX_RenderDevice* device,
                               const CFX_Matrix* matrix) {
   auto* pWriter = GetOnedCode39Writer();
-  CFX_WideString renderCon;
-  if (!pWriter->encodedContents(m_renderContents.AsStringC(), &renderCon))
+  WideString renderCon;
+  if (!pWriter->encodedContents(m_renderContents.AsStringView(), &renderCon))
     return false;
-  return pWriter->RenderDeviceResult(device, matrix, renderCon.AsStringC());
+  return pWriter->RenderDeviceResult(device, matrix, renderCon.AsStringView());
 }
 
 BC_TYPE CBC_Code39::GetType() {