Add static method WebApkIconHasher::DownloadAndComputeMurmur2Hash

chrome/browser/android/webapk/webapk_icon_hasher.cc

Index: chrome/browser/android/webapk/webapk_icon_hasher.cc
diff --git a/chrome/browser/android/webapk/webapk_icon_hasher.cc b/chrome/browser/android/webapk/webapk_icon_hasher.cc
index 2a1a4133f1ef3ee1ce3ccbb7bea2b35a9fb421be..51a44322d5aa32bc25c50ad83de301f598dfe48b 100644
--- a/chrome/browser/android/webapk/webapk_icon_hasher.cc
+++ b/chrome/browser/android/webapk/webapk_icon_hasher.cc
@@ -34,52 +34,57 @@ std::string ComputeMurmur2Hash(const std::string& raw_image_data) {
 
 }  // anonymous namespace
 
-WebApkIconHasher::WebApkIconHasher(
-    net::URLRequestContextGetter* url_request_context_getter,
+// static
+void WebApkIconHasher::DownloadAndComputeMurmur2Hash(
+    net::URLRequestContextGetter* request_context_getter,
     const GURL& icon_url,
-    const Murmur2HashCallback& callback)
-    : url_request_context_getter_(url_request_context_getter),
-      icon_url_(icon_url),
-      callback_(callback) {}
-
-WebApkIconHasher::~WebApkIconHasher() {}
-
-void WebApkIconHasher::DownloadAndComputeMurmur2Hash() {
-  if (!icon_url_.is_valid()) {
+    const Murmur2HashCallback& callback) {
+  if (!icon_url.is_valid()) {
     base::ThreadTaskRunnerHandle::Get()->PostTask(FROM_HERE,
-                                                  base::Bind(callback_, ""));
+                                                  base::Bind(callback, ""));
     return;
   }
 
-  if (icon_url_.SchemeIs(url::kDataScheme)) {
+  if (icon_url.SchemeIs(url::kDataScheme)) {
     std::string mime_type, char_set, data;
     std::string hash;
-    if (net::DataURL::Parse(icon_url_, &mime_type, &char_set, &data) &&
+    if (net::DataURL::Parse(icon_url, &mime_type, &char_set, &data) &&
         !data.empty()) {
       hash = ComputeMurmur2Hash(data);
     }
     base::ThreadTaskRunnerHandle::Get()->PostTask(FROM_HERE,
-                                                  base::Bind(callback_, hash));
+                                                  base::Bind(callback, hash));
     return;
   }
 
+  // The icon hasher will delete itself when it is done.
+  new WebApkIconHasher(request_context_getter, icon_url, callback);
+}
+
+WebApkIconHasher::WebApkIconHasher(
+    net::URLRequestContextGetter* url_request_context_getter,
+    const GURL& icon_url,
+    const Murmur2HashCallback& callback)
+    : callback_(callback) {
   download_timeout_timer_.Start(
       FROM_HERE,
       base::TimeDelta::FromMilliseconds(kDownloadTimeoutInMilliseconds),
       base::Bind(&WebApkIconHasher::OnDownloadTimedOut,
                  base::Unretained(this)));
 
-  url_fetcher_ = net::URLFetcher::Create(icon_url_, net::URLFetcher::GET, this);
-  url_fetcher_->SetRequestContext(url_request_context_getter_);
+  url_fetcher_ = net::URLFetcher::Create(icon_url, net::URLFetcher::GET, this);
+  url_fetcher_->SetRequestContext(url_request_context_getter);
   url_fetcher_->Start();
 }
 
+WebApkIconHasher::~WebApkIconHasher() {}
+
 void WebApkIconHasher::OnURLFetchComplete(const net::URLFetcher* source) {
   download_timeout_timer_.Stop();
 
   if (!source->GetStatus().is_success() ||
       source->GetResponseCode() != net::HTTP_OK) {
-    callback_.Run("");
+    RunCallback("");
     return;
   }
 
@@ -89,12 +94,16 @@ void WebApkIconHasher::OnURLFetchComplete(const net::URLFetcher* source) {
   // browser process is a security bug.
   std::string raw_image_data;
   source->GetResponseAsString(&raw_image_data);
-  callback_.Run(ComputeMurmur2Hash(raw_image_data));
+  RunCallback(ComputeMurmur2Hash(raw_image_data));
 }
 
 void WebApkIconHasher::OnDownloadTimedOut() {
   url_fetcher_.reset();
 
-  base::ThreadTaskRunnerHandle::Get()->PostTask(FROM_HERE,
-                                                base::Bind(callback_, ""));
+  RunCallback("");
+}
+
+void WebApkIconHasher::RunCallback(const std::string& icon_murmur2_hash) {
+  callback_.Run(icon_murmur2_hash);
+  delete this;
 }