Add static method WebApkIconHasher::DownloadAndComputeMurmur2Hash

chrome/browser/android/webapk/webapk_update_data_fetcher.h

Index: chrome/browser/android/webapk/webapk_update_data_fetcher.h
diff --git a/chrome/browser/android/webapk/webapk_update_data_fetcher.h b/chrome/browser/android/webapk/webapk_update_data_fetcher.h
index 8e6ebf864765dfff8fa6b15bc41ee6897d26bf52..2f1db42aa7588ed391b4d4bbea17e7f00aa8cffb 100644
--- a/chrome/browser/android/webapk/webapk_update_data_fetcher.h
+++ b/chrome/browser/android/webapk/webapk_update_data_fetcher.h
@@ -20,7 +20,6 @@ class WebContents;
 
 class GURL;
 struct InstallableData;
-class WebApkIconHasher;
 
 // WebApkUpdateDataFetcher is the C++ counterpart of
 // org.chromium.chrome.browser's WebApkUpdateDataFetcher in Java. It is created
@@ -87,9 +86,6 @@ class WebApkUpdateDataFetcher : public content::WebContentsObserver {
   // The URL for which the installable data is being fetched / was last fetched.
   GURL last_fetched_url_;
 
-  // Downloads app icon and computes Murmur2 hash.
-  std::unique_ptr<WebApkIconHasher> icon_hasher_;
-
   // Downloaded data for |web_manifest_url_|.
   ShortcutInfo info_;
   SkBitmap best_primary_icon_;