Change PDF scaling factor from double to float.

ui/gfx/gdi_util.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef UI_GFX_GDI_UTIL_H_
 #define UI_GFX_GDI_UTIL_H_
 
 #include <vector>
 #include <windows.h>
 
@@ skipping 22 matching lines @@
 void CreateMonochromeBitmapHeader(int width, int height, BITMAPINFOHEADER* hdr);
 
 // Modify the given hrgn by subtracting the given rectangles.
 GFX_EXPORT void SubtractRectanglesFromRegion(
     HRGN hrgn,
     const std::vector<gfx::Rect>& cutouts);
 
 GFX_EXPORT HRGN ConvertPathToHRGN(const gfx::Path& path);
 
 // Calculate scale to fit an entire page on DC.
-GFX_EXPORT double CalculatePageScale(HDC dc, int page_width, int page_height);
+GFX_EXPORT float CalculatePageScale(HDC dc, int page_width, int page_height);
 
 // Apply scaling to the DC.
-GFX_EXPORT bool ScaleDC(HDC dc, double scale_factor);
+GFX_EXPORT bool ScaleDC(HDC dc, float scale_factor);
 
 GFX_EXPORT void StretchDIBits(HDC hdc,
                               int dest_x, int dest_y, int dest_w, int dest_h,
                               int src_x, int src_y, int src_w, int src_h,
                               void* pixels, const BITMAPINFO* bitmap_info);
 
 }  // namespace gfx
 
 #endif  // UI_GFX_GDI_UTIL_H_