Support building Vulkan on Linux.

gyp/shaderc.gyp

 # Copyright 2016 Google Inc.
 #
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 # Builds shaderc for the Vulkan backend
 {
   'variables': {
+    'variables': { # This is the dreaded nested variables dict so that we can
+                   # have dependent variables
+      'conditions': [
+        [ 'CONFIGURATION_NAME == "Release_Developer"', {
+          'shaderc_build_configuration' : 'Release',
+        }, {
+          'shaderc_build_configuration' : '<(CONFIGURATION_NAME)',
+        }],
+        [ 'skia_os == "win"', {
+          'shaderc_lib_name' : 'shaderc_combined.lib',
+        }, {
+          'shaderc_lib_name' : 'libshaderc_combined.a',
+        }],
+        [ 'skia_os == "win"', {
+          'conditions': [
+            [ 'MSVS_VERSION == "2013"', {
+              'shaderc_project_type' : 'MSVS2013',
+            }],
+            [ 'MSVS_VERSION == "2015"', {
+              'shaderc_project_type' : 'MSVS2015',
+            }],
+          ],
+        }, {
+          'shaderc_project_type' : 'ninja',
+        }],
+      ],
+      'shaderc_out_path': '../out/<(CONFIGURATION_NAME)/shaderc_out_<(skia_arch_type)',
+    },
+    # Export out of nested variables.
+    'shaderc_build_configuration': '<(shaderc_build_configuration)',
+    'shaderc_project_type': '<(shaderc_project_type)',
+    'shaderc_out_path': '<(shaderc_out_path)',
+    'shaderc_lib_name': '<(shaderc_lib_name)',
+    
+    # On Windows the library winds up inside a 'Debug' or 'Release' dir, not so
+    # with ninja project build.
     'conditions': [
-      [ 'CONFIGURATION_NAME == "Release_Developer"', {
-        'shaderc_build_type' : 'Release',
+      [ 'skia_os == "win"', {
+        'shaderc_lib_full_path': '<(shaderc_out_path)/libshaderc/<(shaderc_build_configuration)/<(shaderc_lib_name)',
       }, {
-        'shaderc_build_type' : '<(CONFIGURATION_NAME)',
+        'shaderc_lib_full_path': '<(shaderc_out_path)/libshaderc/<(shaderc_lib_name)',
       }],
-      [ 'skia_os == "win"', {
-        'shaderc_lib_name' : 'shaderc_combined.lib',
-      }, {
-        'shaderc_lib_name' : 'libshaderc_combined.a',
-      }],
-      [ 'MSVS_VERSION == "2013"', {
-        'shaderc_project_type' : 'MSVS2013',
-      }],
-      [ 'MSVS_VERSION == "2015"', {
-        'shaderc_project_type' : 'MSVS2015',
-      }],
-    ],
-    'skia_build_type' : '<(CONFIGURATION_NAME)',
+    ]
   },  
   'targets': [  
     {
       # Call out to a python script to build shaderc_combined and then copy it
       # to out/<Configuration>
       'target_name': 'shaderc_combined',
       'type': 'none',
       'actions': [
         {
           'action_name': 'compile_shaderc',
           'inputs': [
             '<!@(python find.py ../third_party/externals/shaderc2 "*")',
             '../tools/build_shaderc.py',
           ],
           'outputs': [
-             '../out/<(skia_build_type)/shaderc_out_<(skia_arch_type)/libshaderc/<(shaderc_build_type)/<(shaderc_lib_name)',
+             '<(shaderc_lib_full_path)',
           ],
-          'action': ['python', '../tools/build_shaderc.py', '-s', '../third_party/externals/shaderc2', '-o', '../out/<(skia_build_type)/shaderc_out_<(skia_arch_type)', '-a', '<(skia_arch_type)', '-t', '<(shaderc_build_type)', '-p', '<(shaderc_project_type)'],
+          'action': ['python', '../tools/build_shaderc.py', '-s', '../third_party/externals/shaderc2', '-o', '<(shaderc_out_path)', '-a', '<(skia_arch_type)', '-t', '<(shaderc_build_configuration)', '-p', '<(shaderc_project_type)'],
         },
       ],     
       'copies': [
         {
-          'destination': '../out/<(skia_build_type)',
-          'files': ['../out/<(skia_build_type)/shaderc_out_<(skia_arch_type)/libshaderc/<(shaderc_build_type)/<(shaderc_lib_name)'],
+          'destination': '../out/<(CONFIGURATION_NAME)',
+          'files': ['<(shaderc_lib_full_path)'],
         },
       ],
       'all_dependent_settings': {
         'link_settings': {
           'libraries': [
-            '-lshaderc_combined',
+            '<(shaderc_lib_name)',
           ],
         },
       },
     },
   ],
 }