platform/loader: move test file definition to platform/loader/BUILD.gn

platform/loader has a BUILD.gn, but it defines only production files,
and files for testing are still defined in platform/BUilD.gn.

This patch moves test file definitions for blink_platform_unittests
from platform/BUILD.gn to platform/loader/BUILD.gn.

BUG=699369

Review-Url: https://codereview.chromium.org/2733253003
Cr-Commit-Position: refs/heads/master@{#455696}

third_party/WebKit/Source/platform/BUILD.gn

@@ -1750,16 +1750,6 @@ test("blink_platform_unittests") {
     "instrumentation/tracing/web_process_memory_dump_test.cc",
     "json/JSONParserTest.cpp",
     "json/JSONValuesTest.cpp",
-    "loader/LinkHeaderTest.cpp",
-    "loader/fetch/ClientHintsPreferencesTest.cpp",
-    "loader/fetch/CrossOriginAccessControlTest.cpp",
-    "loader/fetch/FetchUtilsTest.cpp",
-    "loader/fetch/MemoryCacheCorrectnessTest.cpp",
-    "loader/fetch/MemoryCacheTest.cpp",
-    "loader/fetch/RawResourceTest.cpp",
-    "loader/fetch/ResourceFetcherTest.cpp",
-    "loader/fetch/ResourceLoaderOptionsTest.cpp",
-    "loader/fetch/ResourceTest.cpp",
     "mac/GraphicsContextCanvasTest.mm",
     "mac/VersionUtilMacTest.mm",
     "mojo/CommonCustomTypesStructTraitsTest.cpp",
@@ -1865,6 +1855,7 @@ test("blink_platform_unittests") {
     "//skia",
     "//testing/gmock",
     "//testing/gtest",
+    "//third_party/WebKit/Source/platform/loader:unit_tests",
     "//third_party/WebKit/Source/wtf",
     "//third_party/harfbuzz-ng",
     "//ui/gfx",

third_party/WebKit/Source/platform/loader/BUILD.gn

@@ -84,3 +84,37 @@ source_set("loader") {
     "//v8",
   ]
 }
+
+source_set("unit_tests") {
+  # This target defines test files for blink_platform_unittests and only the
+  # blink_platform_unittests target should depend on it.
+  visibility = [ "//third_party/WebKit/Source/platform:*" ]
+  testonly = true
+
+  # Source files for blink_platform_unittests.
+  sources = [
+    "LinkHeaderTest.cpp",
+    "fetch/ClientHintsPreferencesTest.cpp",
+    "fetch/CrossOriginAccessControlTest.cpp",
+    "fetch/FetchUtilsTest.cpp",
+    "fetch/MemoryCacheCorrectnessTest.cpp",
+    "fetch/MemoryCacheTest.cpp",
+    "fetch/RawResourceTest.cpp",
+    "fetch/ResourceFetcherTest.cpp",
+    "fetch/ResourceLoaderOptionsTest.cpp",
+    "fetch/ResourceTest.cpp",
+  ]
+
+  defines = [ "INSIDE_BLINK" ]
+
+  configs += [
+    "//third_party/WebKit/Source/wtf:wtf_config",
+    "//third_party/WebKit/Source:config",
+  ]
+
+  deps = [
+    "//testing/gmock",
+    "//testing/gtest",
+    "//third_party/WebKit/Source/platform",
+  ]
+}