Summary:
@public
This diff fixes two bugs:
1. When you load a `<WebView/>` with an HTML source string, HTML source doesn't render in the `<WebView/>`. Instead, we get this warning: https://pxl.cl/grz3. Here's what the above page should look like when correctly rendered: https://pxl.cl/grzt
2. Furthermore, you render a blank `<WebView/>` (i.e: with no source prop), it should display a blank page. Instead, we get this warning: https://pxl.cl/grz3
**Bugfix:**
One solution I found was to ensure that `about:blank` is always whitelisted. That way, we don't ever abort navigations to blank pages, which occur when we do:
```ObjectiveC
/** Line 134 in RCTWebView.m */
[_webView loadHTMLString:@"" baseURL:nil];
```
and
```ObjectiveC
/** Line 115 in RCTWebView.m */
if (html) {
NSURL *baseURL = [RCTConvert NSURL:source[@"baseUrl"]];
if (!baseURL) {
baseURL = [NSURL URLWithString:@"about:blank"];
}
[_webView loadHTMLString:html baseURL:baseURL];
return;
}
```
Reviewed By: yungsters, mmmulani
Differential Revision: D9259852
fbshipit-source-id: e1b9673fcd8c3d0df77308df8c4a632a2b596bfb
a5ce1ad767