LibWeb: Make factory method of FileAPI::Blob fallible

Userland/Libraries/LibWeb/Fetch/Body.cpp

@@ -109,7 +109,7 @@ WebIDL::ExceptionOr<JS::Value> package_data(JS::Realm& realm, ByteBuffer bytes,
         // Return a Blob whose contents are bytes and type attribute is mimeType.
         // NOTE: If extracting the mime type returns failure, other browsers set it to an empty string - not sure if that's spec'd.
         auto mime_type_string = mime_type.has_value() ? mime_type->serialized() : DeprecatedString::empty();
-        return FileAPI::Blob::create(realm, move(bytes), move(mime_type_string));
+        return TRY(FileAPI::Blob::create(realm, move(bytes), move(mime_type_string)));
     }
     case PackageDataType::FormData:
         // If mimeType’s essence is "multipart/form-data", then:

Userland/Libraries/LibWeb/FileAPI/Blob.cpp

@@ -15,9 +15,9 @@
 
 namespace Web::FileAPI {
 
-JS::NonnullGCPtr<Blob> Blob::create(JS::Realm& realm, ByteBuffer byte_buffer, DeprecatedString type)
+WebIDL::ExceptionOr<JS::NonnullGCPtr<Blob>> Blob::create(JS::Realm& realm, ByteBuffer byte_buffer, DeprecatedString type)
 {
-    return realm.heap().allocate<Blob>(realm, realm, move(byte_buffer), move(type)).release_allocated_value_but_fixme_should_propagate_errors();
+    return MUST_OR_THROW_OOM(realm.heap().allocate<Blob>(realm, realm, move(byte_buffer), move(type)));
 }
 
 // https://w3c.github.io/FileAPI/#convert-line-endings-to-native

Userland/Libraries/LibWeb/FileAPI/Blob.h

@@ -33,7 +33,7 @@ class Blob : public Bindings::PlatformObject {
 public:
     virtual ~Blob() override;
 
-    static JS::NonnullGCPtr<Blob> create(JS::Realm&, ByteBuffer, DeprecatedString type);
+    static WebIDL::ExceptionOr<JS::NonnullGCPtr<Blob>> create(JS::Realm&, ByteBuffer, DeprecatedString type);
     static WebIDL::ExceptionOr<JS::NonnullGCPtr<Blob>> create(JS::Realm&, Optional<Vector<BlobPart>> const& blob_parts = {}, Optional<BlobPropertyBag> const& options = {});
     static WebIDL::ExceptionOr<JS::NonnullGCPtr<Blob>> construct_impl(JS::Realm&, Optional<Vector<BlobPart>> const& blob_parts = {}, Optional<BlobPropertyBag> const& options = {});
 

Userland/Libraries/LibWeb/XHR/XMLHttpRequest.cpp

@@ -161,7 +161,7 @@ WebIDL::ExceptionOr<JS::Value> XMLHttpRequest::response()
     }
     // 6. Otherwise, if this’s response type is "blob", set this’s response object to a new Blob object representing this’s received bytes with type set to the result of get a final MIME type for this.
     else if (m_response_type == Bindings::XMLHttpRequestResponseType::Blob) {
-        auto blob_part = FileAPI::Blob::create(realm(), m_received_bytes, get_final_mime_type().type());
+        auto blob_part = TRY(FileAPI::Blob::create(realm(), m_received_bytes, get_final_mime_type().type()));
         auto blob = TRY(FileAPI::Blob::create(realm(), Vector<FileAPI::BlobPart> { JS::make_handle(*blob_part) }));
         m_response_object = JS::Value(blob.ptr());
     }