wasm: Make sure all qstdweb classes have val()

These are sometimes needed for passing objects on
to native API.

Change-Id: I89a1a95e6d51932ae3b49eec072261bcb5dbb463
Reviewed-by: Morten Johan Sørvig <morten.sorvig@qt.io>

src/corelib/platform/wasm/qstdweb.cpp

@@ -68,6 +68,11 @@ uint32_t ArrayBuffer::byteLength() const
     return m_arrayBuffer["byteLength"].as<uint32_t>();
 }
 
+emscripten::val ArrayBuffer::val()
+{
+    return m_arrayBuffer;
+}
+
 Blob::Blob(const emscripten::val &blob)
     :m_blob(blob)
 {
@@ -85,7 +90,7 @@ Blob Blob::copyFrom(const char *buffer, uint32_t size)
     Uint8Array contentCopy = Uint8Array::copyFrom(buffer, size);
 
     emscripten::val contentArray = emscripten::val::array();
-    contentArray.call<void>("push", contentCopy.m_uint8Array);
+    contentArray.call<void>("push", contentCopy.val());
     emscripten::val type = emscripten::val::object();
     type.set("type","application/octet-stream");
     return Blob(emscripten::val::global("Blob").new_(contentArray, type));
@@ -172,6 +177,11 @@ std::string File::type() const
     return m_file["type"].as<std::string>();
 }
 
+emscripten::val File::val()
+{
+    return m_file;
+}
+
 FileList::FileList(const emscripten::val &fileList)
     :m_fileList(fileList)
 {
@@ -218,6 +228,11 @@ void FileReader::onAbort(const std::function<void(emscripten::val)> &onAbort)
     m_onAbort.reset(new EventCallback(m_fileReader, "abort", onAbort));
 }
 
+emscripten::val FileReader::val()
+{
+    return m_fileReader;
+}
+
 Uint8Array Uint8Array::heap()
 {
     return Uint8Array(heap_());
@@ -293,6 +308,11 @@ Uint8Array Uint8Array::copyFrom(const char *buffer, uint32_t size)
     return contentCopy;
 }
 
+emscripten::val Uint8Array::val()
+{
+    return m_uint8Array;
+}
+
 emscripten::val Uint8Array::heap_()
 {
     return emscripten::val::module_property("HEAPU8");

src/corelib/platform/wasm/qstdweb_p.h

@@ -62,6 +62,8 @@ namespace qstdweb {
 
     // DOM API in C++, implemented using emscripten val.h and bind.h.
     // This is private API and can be extended and changed as needed.
+    // The API mirrors that of the native API, with some extensions
+    // to ease usage from C++ code.
 
     class ArrayBuffer;
     class Blob;
@@ -76,6 +78,7 @@ namespace qstdweb {
         explicit ArrayBuffer(uint32_t size);
         explicit ArrayBuffer(const emscripten::val &arrayBuffer);
         uint32_t byteLength() const;
+        emscripten::val val();
 
     private:
         friend class Uint8Array;
@@ -106,6 +109,7 @@ namespace qstdweb {
         std::string type() const;
         void stream(uint32_t offset, uint32_t length, char *buffer, const std::function<void ()> &completed) const;
         void stream(char *buffer, const std::function<void ()> &completed) const;
+        emscripten::val val();
 
     private:
         emscripten::val m_file = emscripten::val::undefined();
@@ -119,6 +123,7 @@ namespace qstdweb {
         int length() const;
         File item(int index) const;
         File operator[](int index) const;
+        emscripten::val val();
 
     private:
         emscripten::val m_fileList = emscripten::val::undefined();
@@ -132,6 +137,7 @@ namespace qstdweb {
         void onLoad(const std::function<void(emscripten::val)> &onLoad);
         void onError(const std::function<void(emscripten::val)> &onError);
         void onAbort(const std::function<void(emscripten::val)> &onAbort);
+        emscripten::val val();
 
     private:
         emscripten::val m_fileReader = emscripten::val::global("FileReader").new_();
@@ -156,8 +162,9 @@ namespace qstdweb {
         void copyTo(char *destination) const;
         static void copy(char *destination, const Uint8Array &source);
         static Uint8Array copyFrom(const char *buffer, uint32_t size);
+        emscripten::val val();
+
     private:
-        friend class Blob;
         static emscripten::val heap_();
         static emscripten::val constructor_();
         emscripten::val m_uint8Array = emscripten::val::undefined();
@@ -173,6 +180,7 @@ namespace qstdweb {
         EventCallback(emscripten::val element, const std::string &name,
                       const std::function<void(emscripten::val)> &fn);
         static void activate(emscripten::val event);
+
     private:
         static std::string contextPropertyName(const std::string &eventName);
         emscripten::val m_element = emscripten::val::undefined();