Ensure emnapiInit function is exported

Prevents latest emscripten optimising it away

src/emscripten/common.gypi

@@ -9,8 +9,7 @@
     'default_configuration': 'Release',
     'type': 'executable',
     'cflags': [
-      '-pthread',
-      '-sDEFAULT_TO_CXX=0'
+      '-pthread'
     ],
     'cflags_cc': [
       '-pthread'
@@ -19,6 +18,7 @@
       '--js-library=<!(node -p "require(\'emnapi\').js_library")',
       '-sAUTO_JS_LIBRARIES=0',
       '-sAUTO_NATIVE_LIBRARIES=0',
+      '-sDEFAULT_TO_CXX=0',
       '-sNODEJS_CATCH_EXIT=0',
       '-sNODEJS_CATCH_REJECTION=0'
     ],
@@ -28,7 +28,7 @@
       'EMNAPI_WORKER_POOL_SIZE=1'
     ],
     'include_dirs': [
-      '<!(node -p "require(\'emnapi\').include")'
+      '<!(node -p "require(\'emnapi\').include_dir")'
     ],
     'sources': [
       '<!@(node -p "require(\'emnapi\').sources.map(x => JSON.stringify(path.relative(process.cwd(), x))).join(\' \')")'