Remove PDF JPEG shortcut, since it fails on grayscale JPEGs.

gyp/gmslides.gypi

 # include this gypi to include all the golden master slides.
 {
   'include_dirs': [
     '../gm',
     # include dirs needed by particular GMs
     '../src/utils/debugger',
     '../src/images',
     '../src/lazy',
   ],
   'conditions': [
@@ skipping 81 matching lines @@
         '../gm/getpostextpath.cpp',
         '../gm/giantbitmap.cpp',
         '../gm/glyph_pos.cpp',
         '../gm/glyph_pos_align.cpp',
         '../gm/gradients.cpp',
         '../gm/gradients_2pt_conical.cpp',
         '../gm/gradients_no_texture.cpp',
         '../gm/gradientDirtyLaundry.cpp',
         '../gm/gradient_matrix.cpp',
         '../gm/gradtext.cpp',
+        '../gm/grayscalejpg.cpp',
         '../gm/hairlines.cpp',
         '../gm/hairmodes.cpp',
         '../gm/hittestpath.cpp',
         '../gm/imagealphathreshold.cpp',
         '../gm/imageblur.cpp',
         '../gm/imageblur2.cpp',
         '../gm/imageblurtiled.cpp',
         '../gm/imagemagnifier.cpp',
         '../gm/imageresizetiled.cpp',
         '../gm/inversepaths.cpp',
@@ skipping 127 matching lines @@
         '../gm/shadertext2.cpp',
         '../gm/shadertext3.cpp',
 
         # TODO(reed): Allocates more memory than Android devices are capable of
         # fulfilling. See http://skbug.com/1978
         '../gm/verylargebitmap.cpp',
       ],
     }],
   ],
 }