Cleanup statics in JS classes

This CL removes the static object IDs from each of the CJS_Object
subclasses and moves them to anonymous namespaces. The Spec arrays are
moved to private members of the object classes.

Change-Id: I5dcdb87ef57e4b374b5431580fb55cb75023f8fb
Reviewed-on: https://pdfium-review.googlesource.com/16950
Reviewed-by: Tom Sepez <tsepez@chromium.org>
Commit-Queue: dsinclair <dsinclair@chromium.org>
diff --git a/fpdfsdk/javascript/cjs_display.cpp b/fpdfsdk/javascript/cjs_display.cpp
index afb060b..b196623 100644
--- a/fpdfsdk/javascript/cjs_display.cpp
+++ b/fpdfsdk/javascript/cjs_display.cpp
@@ -12,9 +12,10 @@
                                          {"noView", JSConstSpec::Number, 3, 0},
                                          {0, JSConstSpec::Number, 0, 0}};
 
-int CJS_Display::g_nObjDefnID = -1;
+int CJS_Display::ObjDefnID = -1;
 
+// static
 void CJS_Display::DefineJSObjects(CFXJS_Engine* pEngine, FXJSOBJTYPE eObjType) {
-  g_nObjDefnID = pEngine->DefineObj("display", eObjType, nullptr, nullptr);
-  DefineConsts(pEngine, g_nObjDefnID, ConstSpecs);
+  ObjDefnID = pEngine->DefineObj("display", eObjType, nullptr, nullptr);
+  DefineConsts(pEngine, ObjDefnID, ConstSpecs);
 }