feedv2: choose upload URL depending on channel

We need to pick the action upload endpoint based on
the Chrome channel. While I was here, I refactored some code
to hopefully make it more clear. There was one actual improvement:
we were needlessly copying the request body before gzipping it.

See b/156953207 for some additional information about the api endpoint.

Bug: 1044139
Change-Id: I7ddac54abca3471d68dfffb080ede929ad178848
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2222801Reviewed-by: Ian Wells <iwells@chromium.org>
Commit-Queue: Dan H <harringtond@chromium.org>
Cr-Commit-Position: refs/heads/master@{#774698}

components/feed/core/v2/feed_network_impl.h

@@ -11,6 +11,7 @@
 #include "base/containers/unique_ptr_adapters.h"
 #include "base/memory/scoped_refptr.h"
 #include "components/feed/core/v2/feed_network.h"
+#include "components/version_info/channel.h"
 #include "url/gurl.h"
 
 class PrefService;
@@ -43,7 +44,8 @@ class FeedNetworkImpl : public FeedNetwork {
                   const std::string& api_key,
                   scoped_refptr<network::SharedURLLoaderFactory> loader_factory,
                   const base::TickClock* tick_clock,
-                  PrefService* pref_service);
+                  PrefService* pref_service,
+                  version_info::Channel chrome_channel);
   ~FeedNetworkImpl() override;
   FeedNetworkImpl(const FeedNetworkImpl&) = delete;
   FeedNetworkImpl& operator=(FeedNetworkImpl&) = delete;
@@ -79,6 +81,7 @@ class FeedNetworkImpl : public FeedNetwork {
   Delegate* delegate_;
   signin::IdentityManager* identity_manager_;
   const std::string api_key_;
+  const version_info::Channel chrome_channel_;
   scoped_refptr<network::SharedURLLoaderFactory> loader_factory_;
   const base::TickClock* tick_clock_;
   PrefService* pref_service_;

components/feed/core/v2/feed_network_impl_unittest.cc

@@ -94,7 +94,7 @@ class FeedNetworkTest : public testing::Test {
     feed_network_ = std::make_unique<FeedNetworkImpl>(
         &delegate_, identity_test_env_.identity_manager(), "dummy_api_key",
         shared_url_loader_factory_, task_environment_.GetMockTickClock(),
-        &profile_prefs_);
+        &profile_prefs_, version_info::Channel::STABLE);
   }
 
   FeedNetwork* feed_network() { return feed_network_.get(); }
@@ -410,8 +410,8 @@ TEST_F(FeedNetworkTest, SendActionRequestSendsValidRequest) {
       RespondToActionRequest(GetTestActionResponse(), net::HTTP_OK);
 
   EXPECT_EQ(
-      GURL("https://www.google.com/httpservice/retry/ClankActionUploadService/"
-           "ClankActionUpload?fmt=bin&hl=en"),
+      GURL(
+          "https://discover-pa.googleapis.com/v1/actions:upload?fmt=bin&hl=en"),
       resource_request.url);
 
   EXPECT_EQ("POST", resource_request.method);

components/feed/core/v2/public/feed_service.cc

@@ -145,7 +145,8 @@ FeedService::FeedService(
       base::DefaultTickClock::GetInstance(), profile_prefs);
   feed_network_ = std::make_unique<FeedNetworkImpl>(
       network_delegate_.get(), identity_manager, api_key, url_loader_factory,
-      base::DefaultTickClock::GetInstance(), profile_prefs);
+      base::DefaultTickClock::GetInstance(), profile_prefs,
+      chrome_info.channel);
   store_ = std::make_unique<FeedStore>(std::move(database));
 
   stream_ = std::make_unique<FeedStream>(