Introduces a light version of D8 that links against shared library.

SConstruct

Index: SConstruct
diff --git a/SConstruct b/SConstruct
index 5276ce2cae6e2769cfeecb11f48f5e4f060ed37b..03a615c9a4658274e2657828ecba37641c40e3e0 100644
--- a/SConstruct
+++ b/SConstruct
@@ -773,6 +773,13 @@ PREPARSER_FLAGS = {
 
 
 D8_FLAGS = {
+  'all': {
+    'library:shared': {
+      'CPPDEFINES': ['V8_SHARED'],
+      'LIBS': ['v8'],
+      'LIBPATH': ['.']
+    },
+  },
   'gcc': {
     'all': {
       'CCFLAGS': ['$DIALECTFLAGS', '$WARNINGFLAGS'],
@@ -1370,7 +1377,11 @@ def BuildSpecific(env, mode, env_overrides, tools):
   d8_env = Environment(tools=tools)
   d8_env.Replace(**context.flags['d8'])
   context.ApplyEnvOverrides(d8_env)
-  shell = d8_env.Program('d8' + suffix, object_files + shell_files)
+  if context.options['library'] == 'static':
+    shell = d8_env.Program('d8' + suffix, object_files + shell_files)
+  else:
+    shell = d8_env.Program('d8' + suffix, shell_files)
+    d8_env.Depends(shell, library)
   context.d8_targets.append(shell)
 
   for sample in context.samples: