Fix test slowness introduced by https://codereview.chromium.org/2771793003

chrome/browser/android/webapk/webapk_icon_hasher.h

Index: chrome/browser/android/webapk/webapk_icon_hasher.h
diff --git a/chrome/browser/android/webapk/webapk_icon_hasher.h b/chrome/browser/android/webapk/webapk_icon_hasher.h
index ff54b97738a5bb4dd1ec64c5dc1203fe00d2e1b2..2c5b7b50798ce93d1950ca0bea91daae5888dbc3 100644
--- a/chrome/browser/android/webapk/webapk_icon_hasher.h
+++ b/chrome/browser/android/webapk/webapk_icon_hasher.h
@@ -35,11 +35,17 @@ class WebApkIconHasher : public net::URLFetcherDelegate {
       const GURL& icon_url,
       const Murmur2HashCallback& callback);
 
- private:
-  WebApkIconHasher(
+  static void DownloadAndComputeMurmur2HashWithTimeout(
       net::URLRequestContextGetter* request_context_getter,
       const GURL& icon_url,
+      int timeout_ms,
       const Murmur2HashCallback& callback);
+
+ private:
+  WebApkIconHasher(net::URLRequestContextGetter* request_context_getter,
+                   const GURL& icon_url,
+                   int timeout_ms,
+                   const Murmur2HashCallback& callback);
   ~WebApkIconHasher() override;
 
   // net::URLFetcherDelegate: