Remove wasm compile time option and enable wasm behind a runtime flag.

tools/gyp/v8.gyp

Index: tools/gyp/v8.gyp
diff --git a/tools/gyp/v8.gyp b/tools/gyp/v8.gyp
index 0a834fd5ae92629f16b60daf7a019778ca87644b..f22c4297ad8e49943f6743cafeb13dd7240e70ea 100644
--- a/tools/gyp/v8.gyp
+++ b/tools/gyp/v8.gyp
@@ -648,6 +648,9 @@
         '../../src/compiler/value-numbering-reducer.h',
         '../../src/compiler/verifier.cc',
         '../../src/compiler/verifier.h',
+        '../../src/compiler/wasm-compiler.cc',
+        '../../src/compiler/wasm-compiler.h',
+        '../../src/compiler/wasm-linkage.cc',
         '../../src/compiler/zone-pool.cc',
         '../../src/compiler/zone-pool.h',
         '../../src/compiler.cc',
@@ -1070,6 +1073,24 @@
         '../../src/version.h',
         '../../src/vm-state-inl.h',
         '../../src/vm-state.h',
+        '../../src/wasm/asm-wasm-builder.cc',
+        '../../src/wasm/asm-wasm-builder.h',
+        '../../src/wasm/ast-decoder.cc',
+        '../../src/wasm/ast-decoder.h',
+        '../../src/wasm/decoder.h',
+        '../../src/wasm/encoder.cc',
+        '../../src/wasm/encoder.h',
+        '../../src/wasm/module-decoder.cc',
+        '../../src/wasm/module-decoder.h',
+        '../../src/wasm/wasm-js.cc',
+        '../../src/wasm/wasm-js.h',
+        '../../src/wasm/wasm-macro-gen.h',
+        '../../src/wasm/wasm-module.cc',
+        '../../src/wasm/wasm-module.h',
+        '../../src/wasm/wasm-opcodes.cc',
+        '../../src/wasm/wasm-opcodes.h',
+        '../../src/wasm/wasm-result.cc',
+        '../../src/wasm/wasm-result.h',
         '../../src/zone.cc',
         '../../src/zone.h',
         '../../src/zone-allocator.h',
@@ -1483,31 +1504,6 @@
             }],
           ],
         }],
-        ['v8_wasm!=0', {
-          'sources': [
-            '../../src/compiler/wasm-compiler.cc',
-            '../../src/compiler/wasm-compiler.h',
-            '../../src/compiler/wasm-linkage.cc',
-            '../../src/wasm/asm-wasm-builder.cc',
-            '../../src/wasm/asm-wasm-builder.h',
-            '../../src/wasm/ast-decoder.cc',
-            '../../src/wasm/ast-decoder.h',
-            '../../src/wasm/decoder.h',
-            '../../src/wasm/encoder.cc',
-            '../../src/wasm/encoder.h',
-            '../../src/wasm/module-decoder.cc',
-            '../../src/wasm/module-decoder.h',
-            '../../src/wasm/wasm-js.cc',
-            '../../src/wasm/wasm-js.h',
-            '../../src/wasm/wasm-macro-gen.h',
-            '../../src/wasm/wasm-module.cc',
-            '../../src/wasm/wasm-module.h',
-            '../../src/wasm/wasm-opcodes.cc',
-            '../../src/wasm/wasm-opcodes.h',
-            '../../src/wasm/wasm-result.cc',
-            '../../src/wasm/wasm-result.h',
-          ],
-        }],
       ],
     },
     {