Split fx_dib part 5

Move more classes into their own files.

Change-Id: Ic505be9e406eafb378235216ea19221ce172f32e
Reviewed-on: https://pdfium-review.googlesource.com/3593
Commit-Queue: Nicolás Peña <npm@chromium.org>
Reviewed-by: dsinclair <dsinclair@chromium.org>
diff --git a/BUILD.gn b/BUILD.gn
index 5c12468..fa879d3 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -862,6 +862,10 @@
     "core/fxge/cfx_substfont.h",
     "core/fxge/cfx_unicodeencoding.h",
     "core/fxge/cfx_windowsdevice.h",
+    "core/fxge/dib/cfx_bitmapcomposer.cpp",
+    "core/fxge/dib/cfx_bitmapcomposer.h",
+    "core/fxge/dib/cfx_bitmapstorer.cpp",
+    "core/fxge/dib/cfx_bitmapstorer.h",
     "core/fxge/dib/cfx_dibextractor.cpp",
     "core/fxge/dib/cfx_dibextractor.h",
     "core/fxge/dib/cfx_dibitmap.cpp",
@@ -872,12 +876,13 @@
     "core/fxge/dib/cfx_filtereddib.h",
     "core/fxge/dib/cfx_imagerenderer.cpp",
     "core/fxge/dib/cfx_imagerenderer.h",
+    "core/fxge/dib/cfx_imagestretcher.cpp",
+    "core/fxge/dib/cfx_imagestretcher.h",
     "core/fxge/dib/cfx_imagetransformer.cpp",
     "core/fxge/dib/cfx_imagetransformer.h",
     "core/fxge/dib/cfx_scanlinecompositor.cpp",
     "core/fxge/dib/cfx_scanlinecompositor.h",
     "core/fxge/dib/dib_int.h",
-    "core/fxge/dib/fx_dib_composite.cpp",
     "core/fxge/dib/fx_dib_convert.cpp",
     "core/fxge/dib/fx_dib_engine.cpp",
     "core/fxge/dib/fx_dib_main.cpp",