Move ImageFetcher to its own target.

ios/chrome/browser/net/BUILD.gn

Index: ios/chrome/browser/net/BUILD.gn
diff --git a/ios/chrome/browser/net/BUILD.gn b/ios/chrome/browser/net/BUILD.gn
index 4b26d7f72c7596c18f820d93b31ee35db071b584..f97a196589cfcf1a00e4f2c1e1b3adfc10fcf65f 100644
--- a/ios/chrome/browser/net/BUILD.gn
+++ b/ios/chrome/browser/net/BUILD.gn
@@ -15,7 +15,6 @@ source_set("net") {
     "http_server_properties_manager_factory.cc",
     "http_server_properties_manager_factory.h",
     "image_fetcher.h",

[sdefresne, 2016/11/22 14:03:52]

You also want to move image_fetcher.h to the "image_fetcher" target (see comment
below first).

[gambard, 2016/11/22 14:25:11]

Done.

-    "image_fetcher.mm",
     "ios_chrome_http_user_agent_settings.h",
     "ios_chrome_http_user_agent_settings.mm",
     "ios_chrome_network_delegate.cc",
@@ -43,6 +42,7 @@ source_set("net") {
     "//ios/chrome/browser",
     "//ios/chrome/browser/browser_state",
     "//ios/chrome/browser/browsing_data",
+    "//ios/chrome/browser/net/image_fetcher",

[sdefresne, 2016/11/22 14:03:52]

You don't have to move the files, just create a target named "image_fetcher" in
the current BUILD.gn file, and the dependency will be on
"//ios/chrome/browser/net:image_fetcher".

[gambard, 2016/11/22 14:25:12]

Done.

     "//ios/chrome/browser/webp_transcode",
     "//ios/net",
     "//ios/web",
@@ -60,11 +60,9 @@ source_set("test_support") {
   testonly = true
   sources = [
     "mock_image_fetcher.h",
-    "mock_image_fetcher.mm",
   ]
   deps = [
-    ":net",
-    "//testing/gmock",
+    "//ios/chrome/browser/net/image_fetcher:test_support",
   ]
 }
 
@@ -72,7 +70,6 @@ source_set("unit_tests") {
   testonly = true
   sources = [
     "cookie_util_unittest.mm",
-    "image_fetcher_unittest.mm",
     "metrics_network_client_unittest.mm",

[sdefresne, 2016/11/22 14:03:52]

We do not need to change "unit_tests" target, as only the test app depends on
it, so no risk of circular dependencies.

[gambard, 2016/11/22 14:25:12]

Done.

     "retryable_url_fetcher_unittest.mm",
   ]