wasm - replace the WLL section with support to skip all unknown sections.

src/wasm/module-decoder.cc

Index: src/wasm/module-decoder.cc
diff --git a/src/wasm/module-decoder.cc b/src/wasm/module-decoder.cc
index 62b000da2bfd8b3d5df0b2c612a027ffe0a64946..861c275ce93ab1066e41cdbaab8b415f1d2ff222 100644
--- a/src/wasm/module-decoder.cc
+++ b/src/wasm/module-decoder.cc
@@ -234,23 +234,16 @@ class ModuleDecoder : public Decoder {
           }
           break;
         }
-        case kDeclWLL: {
-          // Reserved for experimentation by the Web Low-level Language project
-          // which is augmenting the binary encoding with source code meta
-          // information. This section does not affect the semantics of the code
-          // and can be ignored by the runtime. https://github.com/JSStats/wll
-          int length = 0;
-          uint32_t section_size = consume_u32v(&length, "section size");
+        default:
+          // All other sections are ignored and skipped. Known experimental
+          // sections: 0x11 WLL https://github.com/JSStats/wll
+          uint32_t section_size = consume_u32("section size");
           if (pc_ + section_size > limit_ || pc_ + section_size < pc_) {
-            error(pc_ - length, "invalid section size");
+            error(pc_ - 4, "invalid section size");
             break;
           }
           pc_ += section_size;
           break;
-        }
-        default:
-          error(pc_ - 1, nullptr, "unrecognized section 0x%02x", section);
-          break;
       }
     }