Deprecated FPDF_RENDER_READER in favour of FPDF_RENDER_READY

The use of Ready makes more sense then Reader for the constants. Rename
and deprecate the old one.

Bug: pdfium:830
Change-Id: I80b970f29a21068b41993c1880d81d406c3108e0
Reviewed-on: https://pdfium-review.googlesource.com/8790
Reviewed-by: Henrique Nakashima <hnakashima@chromium.org>
Commit-Queue: dsinclair <dsinclair@chromium.org>
diff --git a/fpdfsdk/fpdf_progressive.cpp b/fpdfsdk/fpdf_progressive.cpp
index abddcd4..1b10a11 100644
--- a/fpdfsdk/fpdf_progressive.cpp
+++ b/fpdfsdk/fpdf_progressive.cpp
@@ -20,7 +20,7 @@
 #include "third_party/base/ptr_util.h"
 
 // These checks are here because core/ and public/ cannot depend on each other.
-static_assert(CPDF_ProgressiveRenderer::Ready == FPDF_RENDER_READER,
+static_assert(CPDF_ProgressiveRenderer::Ready == FPDF_RENDER_READY,
               "CPDF_ProgressiveRenderer::Ready value mismatch");
 static_assert(CPDF_ProgressiveRenderer::ToBeContinued ==
                   FPDF_RENDER_TOBECONTINUED,