Rename PngModule to PngDecoder.

Change-Id: I11f79d77fedbe5c2f086b642309e3f4ecdf2c7ef
Reviewed-on: https://pdfium-review.googlesource.com/c/pdfium/+/69918
Commit-Queue: Lei Zhang <thestig@chromium.org>
Reviewed-by: Tom Sepez <tsepez@chromium.org>
diff --git a/core/fxcodec/BUILD.gn b/core/fxcodec/BUILD.gn
index 34023c6..b168112 100644
--- a/core/fxcodec/BUILD.gn
+++ b/core/fxcodec/BUILD.gn
@@ -113,8 +113,8 @@
     }
     if (pdf_enable_xfa_png) {
       sources += [
-        "png/pngmodule.cpp",
-        "png/pngmodule.h",
+        "png/png_decoder.cpp",
+        "png/png_decoder.h",
       ]
       deps += [ "../../third_party:png" ]
     }
diff --git a/core/fxcodec/png/pngmodule.cpp b/core/fxcodec/png/png_decoder.cpp
similarity index 92%
rename from core/fxcodec/png/pngmodule.cpp
rename to core/fxcodec/png/png_decoder.cpp
index b254d33..0e4abc4 100644
--- a/core/fxcodec/png/pngmodule.cpp
+++ b/core/fxcodec/png/png_decoder.cpp
@@ -4,7 +4,7 @@
 
 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
 
-#include "core/fxcodec/png/pngmodule.h"
+#include "core/fxcodec/png/png_decoder.h"
 
 #include <algorithm>
 
@@ -25,12 +25,12 @@
 
 class CPngContext final : public ProgressiveDecoderIface::Context {
  public:
-  explicit CPngContext(PngModule::Delegate* pDelegate);
+  explicit CPngContext(PngDecoder::Delegate* pDelegate);
   ~CPngContext() override;
 
   png_structp m_pPng = nullptr;
   png_infop m_pInfo = nullptr;
-  UnownedPtr<PngModule::Delegate> const m_pDelegate;
+  UnownedPtr<PngDecoder::Delegate> const m_pDelegate;
   char m_szLastError[PNG_ERROR_SIZE];
 };
 
@@ -172,7 +172,7 @@
 
 }  // extern "C"
 
-CPngContext::CPngContext(PngModule::Delegate* pDelegate)
+CPngContext::CPngContext(PngDecoder::Delegate* pDelegate)
     : m_pDelegate(pDelegate) {
   memset(m_szLastError, 0, sizeof(m_szLastError));
 }
@@ -185,7 +185,7 @@
 namespace fxcodec {
 
 // static
-std::unique_ptr<ProgressiveDecoderIface::Context> PngModule::StartDecode(
+std::unique_ptr<ProgressiveDecoderIface::Context> PngDecoder::StartDecode(
     Delegate* pDelegate) {
   auto p = pdfium::MakeUnique<CPngContext>(pDelegate);
   p->m_pPng =
@@ -208,9 +208,9 @@
 }
 
 // static
-bool PngModule::ContinueDecode(ProgressiveDecoderIface::Context* pContext,
-                               RetainPtr<CFX_CodecMemory> codec_memory,
-                               CFX_DIBAttribute* pAttribute) {
+bool PngDecoder::ContinueDecode(ProgressiveDecoderIface::Context* pContext,
+                                RetainPtr<CFX_CodecMemory> codec_memory,
+                                CFX_DIBAttribute* pAttribute) {
   auto* ctx = static_cast<CPngContext*>(pContext);
   if (setjmp(png_jmpbuf(ctx->m_pPng))) {
     if (pAttribute &&
diff --git a/core/fxcodec/png/pngmodule.h b/core/fxcodec/png/png_decoder.h
similarity index 81%
rename from core/fxcodec/png/pngmodule.h
rename to core/fxcodec/png/png_decoder.h
index b2c0bfd..3eca876 100644
--- a/core/fxcodec/png/pngmodule.h
+++ b/core/fxcodec/png/png_decoder.h
@@ -4,8 +4,8 @@
 
 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
 
-#ifndef CORE_FXCODEC_PNG_PNGMODULE_H_
-#define CORE_FXCODEC_PNG_PNGMODULE_H_
+#ifndef CORE_FXCODEC_PNG_PNG_DECODER_H_
+#define CORE_FXCODEC_PNG_PNG_DECODER_H_
 
 #include <memory>
 
@@ -17,7 +17,7 @@
 
 namespace fxcodec {
 
-class PngModule {
+class PngDecoder {
  public:
   class Delegate {
    public:
@@ -42,13 +42,13 @@
                              RetainPtr<CFX_CodecMemory> codec_memory,
                              CFX_DIBAttribute* pAttribute);
 
-  PngModule() = delete;
-  PngModule(const PngModule&) = delete;
-  PngModule& operator=(const PngModule&) = delete;
+  PngDecoder() = delete;
+  PngDecoder(const PngDecoder&) = delete;
+  PngDecoder& operator=(const PngDecoder&) = delete;
 };
 
 }  // namespace fxcodec
 
-using PngModule = fxcodec::PngModule;
+using PngDecoder = fxcodec::PngDecoder;
 
-#endif  // CORE_FXCODEC_PNG_PNGMODULE_H_
+#endif  // CORE_FXCODEC_PNG_PNG_DECODER_H_
diff --git a/core/fxcodec/progressivedecoder.cpp b/core/fxcodec/progressivedecoder.cpp
index 0438797..feb5fde 100644
--- a/core/fxcodec/progressivedecoder.cpp
+++ b/core/fxcodec/progressivedecoder.cpp
@@ -1190,13 +1190,13 @@
 
 bool ProgressiveDecoder::PngDetectImageTypeInBuffer(
     CFX_DIBAttribute* pAttribute) {
-  m_pPngContext = PngModule::StartDecode(this);
+  m_pPngContext = PngDecoder::StartDecode(this);
   if (!m_pPngContext) {
     m_status = FXCODEC_STATUS_ERR_MEMORY;
     return false;
   }
-  while (PngModule::ContinueDecode(m_pPngContext.get(), m_pCodecMemory,
-                                   pAttribute)) {
+  while (PngDecoder::ContinueDecode(m_pPngContext.get(), m_pCodecMemory,
+                                    pAttribute)) {
     uint32_t remain_size = static_cast<uint32_t>(m_pFile->GetSize()) - m_offSet;
     uint32_t input_size = std::min<uint32_t>(remain_size, kBlockSize);
     if (input_size == 0) {
@@ -1224,7 +1224,7 @@
 
 FXCODEC_STATUS ProgressiveDecoder::PngStartDecode(
     const RetainPtr<CFX_DIBitmap>& pDIBitmap) {
-  m_pPngContext = PngModule::StartDecode(this);
+  m_pPngContext = PngDecoder::StartDecode(this);
   if (!m_pPngContext) {
     m_pDeviceBitmap = nullptr;
     m_pFile = nullptr;
@@ -1286,8 +1286,8 @@
       return m_status;
     }
     m_offSet += input_size;
-    bResult =
-        PngModule::ContinueDecode(m_pPngContext.get(), m_pCodecMemory, nullptr);
+    bResult = PngDecoder::ContinueDecode(m_pPngContext.get(), m_pCodecMemory,
+                                         nullptr);
     if (!bResult) {
       m_pDeviceBitmap = nullptr;
       m_pFile = nullptr;
diff --git a/core/fxcodec/progressivedecoder.h b/core/fxcodec/progressivedecoder.h
index 53d3413..e45cc9f 100644
--- a/core/fxcodec/progressivedecoder.h
+++ b/core/fxcodec/progressivedecoder.h
@@ -28,7 +28,7 @@
 #endif  // PDF_ENABLE_XFA_GIF
 
 #ifdef PDF_ENABLE_XFA_PNG
-#include "core/fxcodec/png/pngmodule.h"
+#include "core/fxcodec/png/png_decoder.h"
 #endif  // PDF_ENABLE_XFA_PNG
 
 class CFX_DIBitmap;
@@ -49,7 +49,7 @@
     public GifModule::Delegate,
 #endif  // PDF_ENABLE_XFA_GIF
 #ifdef PDF_ENABLE_XFA_PNG
-    public PngModule::Delegate,
+    public PngDecoder::Delegate,
 #endif  // PDF_ENABLE_XFA_PNG
     public Dummy {
  public:
@@ -141,7 +141,7 @@
   };
 
 #ifdef PDF_ENABLE_XFA_PNG
-  // PngModule::Delegate
+  // PngDecoder::Delegate
   bool PngReadHeader(int width,
                      int height,
                      int bpc,