Use native Wasm+Webpack support for Rust codecs

This delegates loading of Wasm modules to Webpack itself, making wrapper code simpler.

Emscripten-generated modules are still using custom loading glue as they're not compatible with Webpack.

codecs/resize/pkg/resize.js

@@ -1,95 +1,50 @@
-(function() {
-    const __exports = {};
-    let wasm;
+import * as wasm from './resize_bg.wasm';
 
-    let cachegetUint8Memory = null;
-    function getUint8Memory() {
-        if (cachegetUint8Memory === null || cachegetUint8Memory.buffer !== wasm.memory.buffer) {
-            cachegetUint8Memory = new Uint8Array(wasm.memory.buffer);
-        }
-        return cachegetUint8Memory;
+let cachegetUint8Memory = null;
+function getUint8Memory() {
+    if (cachegetUint8Memory === null || cachegetUint8Memory.buffer !== wasm.memory.buffer) {
+        cachegetUint8Memory = new Uint8Array(wasm.memory.buffer);
     }
+    return cachegetUint8Memory;
+}
 
-    let WASM_VECTOR_LEN = 0;
+let WASM_VECTOR_LEN = 0;
 
-    function passArray8ToWasm(arg) {
-        const ptr = wasm.__wbindgen_malloc(arg.length * 1);
-        getUint8Memory().set(arg, ptr / 1);
-        WASM_VECTOR_LEN = arg.length;
-        return ptr;
+function passArray8ToWasm(arg) {
+    const ptr = wasm.__wbindgen_malloc(arg.length * 1);
+    getUint8Memory().set(arg, ptr / 1);
+    WASM_VECTOR_LEN = arg.length;
+    return ptr;
+}
+
+let cachegetInt32Memory = null;
+function getInt32Memory() {
+    if (cachegetInt32Memory === null || cachegetInt32Memory.buffer !== wasm.memory.buffer) {
+        cachegetInt32Memory = new Int32Array(wasm.memory.buffer);
     }
+    return cachegetInt32Memory;
+}
 
-    let cachegetInt32Memory = null;
-    function getInt32Memory() {
-        if (cachegetInt32Memory === null || cachegetInt32Memory.buffer !== wasm.memory.buffer) {
-            cachegetInt32Memory = new Int32Array(wasm.memory.buffer);
-        }
-        return cachegetInt32Memory;
-    }
+function getArrayU8FromWasm(ptr, len) {
+    return getUint8Memory().subarray(ptr / 1, ptr / 1 + len);
+}
+/**
+* @param {Uint8Array} input_image
+* @param {number} input_width
+* @param {number} input_height
+* @param {number} output_width
+* @param {number} output_height
+* @param {number} typ_idx
+* @param {boolean} premultiply
+* @param {boolean} color_space_conversion
+* @returns {Uint8Array}
+*/
+export function resize(input_image, input_width, input_height, output_width, output_height, typ_idx, premultiply, color_space_conversion) {
+    const retptr = 8;
+    const ret = wasm.resize(retptr, passArray8ToWasm(input_image), WASM_VECTOR_LEN, input_width, input_height, output_width, output_height, typ_idx, premultiply, color_space_conversion);
+    const memi32 = getInt32Memory();
+    const v0 = getArrayU8FromWasm(memi32[retptr / 4 + 0], memi32[retptr / 4 + 1]).slice();
+    wasm.__wbindgen_free(memi32[retptr / 4 + 0], memi32[retptr / 4 + 1] * 1);
+    return v0;
+}
 
-    function getArrayU8FromWasm(ptr, len) {
-        return getUint8Memory().subarray(ptr / 1, ptr / 1 + len);
-    }
-    /**
-    * @param {Uint8Array} input_image
-    * @param {number} input_width
-    * @param {number} input_height
-    * @param {number} output_width
-    * @param {number} output_height
-    * @param {number} typ_idx
-    * @param {boolean} premultiply
-    * @param {boolean} color_space_conversion
-    * @returns {Uint8Array}
-    */
-    __exports.resize = function(input_image, input_width, input_height, output_width, output_height, typ_idx, premultiply, color_space_conversion) {
-        const retptr = 8;
-        const ret = wasm.resize(retptr, passArray8ToWasm(input_image), WASM_VECTOR_LEN, input_width, input_height, output_width, output_height, typ_idx, premultiply, color_space_conversion);
-        const memi32 = getInt32Memory();
-        const v0 = getArrayU8FromWasm(memi32[retptr / 4 + 0], memi32[retptr / 4 + 1]).slice();
-        wasm.__wbindgen_free(memi32[retptr / 4 + 0], memi32[retptr / 4 + 1] * 1);
-        return v0;
-    };
-
-    function init(module) {
-
-        let result;
-        const imports = {};
-
-        if (module instanceof URL || typeof module === 'string' || module instanceof Request) {
-
-            const response = fetch(module);
-            if (typeof WebAssembly.instantiateStreaming === 'function') {
-                result = WebAssembly.instantiateStreaming(response, imports)
-                .catch(e => {
-                    console.warn("`WebAssembly.instantiateStreaming` failed. Assuming this is because your server does not serve wasm with `application/wasm` MIME type. Falling back to `WebAssembly.instantiate` which is slower. Original error:\n", e);
-                    return response
-                    .then(r => r.arrayBuffer())
-                    .then(bytes => WebAssembly.instantiate(bytes, imports));
-                });
-            } else {
-                result = response
-                .then(r => r.arrayBuffer())
-                .then(bytes => WebAssembly.instantiate(bytes, imports));
-            }
-        } else {
-
-            result = WebAssembly.instantiate(module, imports)
-            .then(result => {
-                if (result instanceof WebAssembly.Instance) {
-                    return { instance: result, module };
-                } else {
-                    return result;
-                }
-            });
-        }
-        return result.then(({instance, module}) => {
-            wasm = instance.exports;
-            init.__wbindgen_wasm_module = module;
-
-            return wasm;
-        });
-    }
-
-    self.wasm_bindgen = Object.assign(init, __exports);
-
-})();