Switch the background color in PDF Viewer when using Material Design

pdf/pdf_engine.h

Index: pdf/pdf_engine.h
diff --git a/pdf/pdf_engine.h b/pdf/pdf_engine.h
index 884daab24aa0fc0c05ca4bb5522be15dff33c432..e8434595ddb5edd0202329404cd26839d433611f 100644
--- a/pdf/pdf_engine.h
+++ b/pdf/pdf_engine.h
@@ -31,8 +31,6 @@ class InputEvent;
 class VarDictionary;
 }
 
-const uint32 kBackgroundColor = 0xFFCCCCCC;
-
 namespace chrome_pdf {
 
 class Stream;
@@ -248,6 +246,11 @@ class PDFEngine {
   // Returns number of copies to be printed.
   virtual int GetCopiesToPrint() = 0;
 
+  // Retrieve the background color of the PDF viewer.
+  virtual uint32 GetBackgroundColor() = 0;
+  // Set the background color of the PDF viewer.
+  virtual void SetBackgroundColor(uint32 background_color) = 0;
+
   // Returns a VarArray of Bookmarks, each a VarDictionary containing the
   // following key/values:
   // - "title" - a string Var.