wasm: add setting type to Blob

Blobs can be any mime type, add function that sets up mime type

This allows Safari to play videos that are Blobs

Pick-to: 6.5
Change-Id: Ide63851934058935d94f42721b246d832e3bcb85
Reviewed-by: Mikołaj Boc <Mikolaj.Boc@qt.io>

src/corelib/platform/wasm/qstdweb.cpp

@@ -512,18 +512,23 @@ uint32_t Blob::size() const
     return m_blob["size"].as<uint32_t>();
 }
 
-// Copies content from the given buffer into a Blob object
-Blob Blob::copyFrom(const char *buffer, uint32_t size)
+Blob Blob::copyFrom(const char *buffer, uint32_t size, std::string mimeType)
 {
     Uint8Array contentCopy = Uint8Array::copyFrom(buffer, size);
 
     emscripten::val contentArray = emscripten::val::array();
     contentArray.call<void>("push", contentCopy.val());
     emscripten::val type = emscripten::val::object();
-    type.set("type","application/octet-stream");
+    type.set("type", std::move(mimeType));
     return Blob(emscripten::val::global("Blob").new_(contentArray, type));
 }
 
+// Copies content from the given buffer into a Blob object
+Blob Blob::copyFrom(const char *buffer, uint32_t size)
+{
+    return copyFrom(buffer, size, "application/octet-stream");
+}
+
 emscripten::val Blob::val()
 {
     return m_blob;

src/corelib/platform/wasm/qstdweb_p.h

@@ -64,6 +64,7 @@ namespace qstdweb {
     public:
         explicit Blob(const emscripten::val &blob);
         uint32_t size() const;
+        static Blob copyFrom(const char *buffer, uint32_t size, std::string mimeType);
         static Blob copyFrom(const char *buffer, uint32_t size);
         emscripten::val val();
         std::string type() const;