Fix a bug with handling infinities in the flex formatter

Source/Core/Layout/FlexFormattingContext.cpp

@@ -119,16 +119,18 @@ UniquePtr<LayoutBox> FlexFormattingContext::Format(ContainerBox* parent_containe
 }
 
 Vector2f FlexFormattingContext::GetMaxContentSize(Element *element) {
-	RootBox root(Vector2f(FLT_MAX, FLT_MAX));
-	Vector2f containing_block(FLT_MAX, FLT_MAX);
+	// A large but finite number is used here, because the flexbox formatting algorithm
+	// needs to round numbers, and it doesn't support infinities.
+	Vector2f infinity(10000.0f, 10000.0f);
+	RootBox root(infinity);
 	auto flex_container_box = MakeUnique<FlexContainer>(element, &root);
 
 	FlexFormattingContext context;
 	context.flex_container_box = flex_container_box.get();
 	context.element_flex = element;
-	context.flex_available_content_size = Vector2f(-1, -1);
-	context.flex_content_containing_block = Vector2f(-1, -1);
-	context.flex_max_size = Vector2f(FLT_MAX, FLT_MAX);
+	context.flex_available_content_size = infinity;
+	context.flex_content_containing_block = infinity;
+	context.flex_max_size = infinity;
 
 	// Format the flexbox and all its children.
 	Vector2f flex_resulting_content_size, content_overflow_size;