[Fuchsia] Rename //fuchsia/http:common to //fuchsia/http:core.

Other similar targets under the //fuchsia directory are referred to as
"core" rather than "common". This target is renamed for consistency.

Bug: 922635
Change-Id: I84e54aa5183f7590f0caa88b0f943e88ee9aea56
Reviewed-on: https://chromium-review.googlesource.com/c/1489519
Commit-Queue: Kevin Marshall <kmarshall@chromium.org>
Reviewed-by: Sergey Ulanov <sergeyu@chromium.org>
Reviewed-by: Kevin Marshall <kmarshall@chromium.org>
Cr-Commit-Position: refs/heads/master@{#636100}

fuchsia/http/BUILD.gn

@@ -10,7 +10,7 @@ import("//build/util/process_version.gni")
 import("//testing/test.gni")
 import("//tools/grit/repack.gni")
 
-source_set("common") {
+source_set("core") {
   sources = [
     "http_service_impl.cc",
     "http_service_impl.h",
@@ -31,7 +31,7 @@ executable("http_exe") {
     "http_service_main.cc",
   ]
   deps = [
-    ":common",
+    ":core",
   ]
   visibility = [ ":*" ]
 }
@@ -52,7 +52,7 @@ test("http_service_tests") {
     "http_service_unittest.cc",
   ]
   deps = [
-    ":common",
+    ":core",
     "//base/test:run_all_unittests",
     "//net:test_support",
     "//testing/gtest",