Remove unused SampleTests.cpp source file.

gyp/SampleApp.gyp

 #
 {
   'variables': {
     #manually set sample_pdf_file_viewer to 1 to have the PdfViewer in SampleApp
     'sample_pdf_file_viewer%': 0,
   },
   'targets': [
     {
       'target_name': 'SampleApp',
       'type': 'executable',
@@ skipping 90 matching lines @@
         '../samplecode/SamplePolyToPoly.cpp',
         '../samplecode/SampleRegion.cpp',
         '../samplecode/SampleRepeatTile.cpp',
         '../samplecode/SampleRotateCircles.cpp',
         '../samplecode/SampleShaders.cpp',
         '../samplecode/SampleShaderText.cpp',
         '../samplecode/SampleSkLayer.cpp',
         '../samplecode/SampleSlides.cpp',
         '../samplecode/SampleStringArt.cpp',
         '../samplecode/SampleStrokePath.cpp',
-        '../samplecode/SampleTests.cpp',
         '../samplecode/SampleText.cpp',
         '../samplecode/SampleTextAlpha.cpp',
         '../samplecode/SampleTextBox.cpp',
         '../samplecode/SampleTextOnPath.cpp',
         '../samplecode/SampleTextureDomain.cpp',
         '../samplecode/SampleTiling.cpp',
         '../samplecode/SampleTinyBitmap.cpp',
         '../samplecode/SampleUnitMapper.cpp',
         '../samplecode/SampleUnpremul.cpp',
         '../samplecode/SampleVertices.cpp',
@@ skipping 17 matching lines @@
         # TiledPipeController
         '../src/pipe/utils/SamplePipeControllers.h',
         '../src/pipe/utils/SamplePipeControllers.cpp',
 
         # Lua
         '../src/utils/SkLuaCanvas.cpp',
         '../src/utils/SkLua.cpp',
       ],
       'sources!': [
         '../samplecode/SampleSkLayer.cpp', #relies on SkMatrix44 which doesn't compile
-        '../samplecode/SampleTests.cpp',   #includes unknown file SkShaderExtras.h
         '../samplecode/SampleWarp.cpp',
         '../samplecode/SampleFontCache.cpp',
       ],
       'dependencies': [
         'skia_lib.gyp:skia_lib',
         'views.gyp:views',
         'animator.gyp:animator',
         'xml.gyp:xml',
         'experimental.gyp:experimental',
         'pdf.gyp:pdf',
@@ skipping 156 matching lines @@
         }],
       ],
       'msvs_settings': {
         'VCLinkerTool': {
           'SubSystem': '2',
         },
       },
     },
   ],
 }