Changes to merge vulkan code

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1711793004

Review URL: https://codereview.chromium.org/1711793004
diff --git a/gyp/common_variables.gypi b/gyp/common_variables.gypi
index abbfaac..6f4ac87 100644
--- a/gyp/common_variables.gypi
+++ b/gyp/common_variables.gypi
@@ -41,7 +41,6 @@
     'skia_mojo%': '0',
 
     'variables': {  # level 2
-
       # Variables needed by conditions list within the level-2 variables dict.
       'variables': {  # level 3
         'variables': { # level 4
@@ -52,7 +51,7 @@
           'skia_os%': '<(OS)',
         },
         'skia_os%': '<(skia_os)',
-
+        'vulkan_merged_into_skia': '1',
         'skia_android_framework%': 0,
         'conditions' : [
           [ 'skia_os in ["linux", "freebsd", "openbsd", "solaris", "mac"]', {
@@ -83,7 +82,7 @@
       'arm_version%': '<(arm_version)',
       'arm_neon%': '<(arm_neon)',
       'skia_egl%': '<(skia_egl)',
-
+      'vulkan_merged_into_skia%': '<(vulkan_merged_into_skia)',
       'conditions': [
         [ 'skia_android_framework == 1', {
           'skia_os%': 'android',
@@ -253,6 +252,7 @@
     'skia_fast%': 0,
     'skia_dump_stats%': 0,
     'skia_build_server%': 0,
+    'vulkan_merged_into_skia%': '<(vulkan_merged_into_skia)',
     'skia_fast_flags': [
         '-O3',                   # Even for Debug builds.
         '-march=native',         # Use all features of and optimize for THIS machine.