Move RegisterPathProvider() from ContentTestSuite to ContentTestSuiteBase

Fixes network_service_content_browsertests RenderThreadImplBrowserTest.NonResourceDispatchIPCTasksDontGoThroughScheduler
failing to find the utility service process exe on Windows, like:
[FATAL:utility_process_host.cc(263)] Check failed: false. Unable to get utility process binary name.

Bug: 876947
Cq-Include-Trybots: luci.chromium.try:linux_mojo
Change-Id: Ia7f51366e4b4db27ec8c3bbee3d57866c1bd67b9
Reviewed-on: https://chromium-review.googlesource.com/1185628
Commit-Queue: Matt Mueller <mattm@chromium.org>
Reviewed-by: John Abd-El-Malek <jam@chromium.org>
Cr-Commit-Position: refs/heads/master@{#586063}

content/public/test/content_test_suite_base.cc

@@ -15,6 +15,7 @@
 #include "content/common/url_schemes.h"
 #include "content/gpu/in_process_gpu_thread.h"
 #include "content/public/common/content_client.h"
+#include "content/public/common/content_paths.h"
 #include "content/renderer/in_process_renderer_thread.h"
 #include "content/utility/in_process_utility_thread.h"
 #include "testing/gtest/include/gtest/gtest.h"
@@ -50,6 +51,8 @@ ContentTestSuiteBase::ContentTestSuiteBase(int argc, char** argv)
 void ContentTestSuiteBase::Initialize() {
   base::TestSuite::Initialize();
 
+  RegisterPathProvider();
+
 #if defined(V8_USE_EXTERNAL_STARTUP_DATA)
   gin::V8Initializer::LoadV8Snapshot(kSnapshotType);
   gin::V8Initializer::LoadV8Natives();

content/test/content_test_suite.cc

@@ -11,7 +11,6 @@
 #include "base/macros.h"
 #include "build/build_config.h"
 #include "content/public/common/content_client.h"
-#include "content/public/common/content_paths.h"
 #include "content/public/test/test_content_client_initializer.h"
 #include "gpu/config/gpu_info_collector.h"
 #include "gpu/config/gpu_preferences.h"
@@ -81,7 +80,6 @@ void ContentTestSuite::Initialize() {
     ContentClient client;
     ContentTestSuiteBase::RegisterContentSchemes(&client);
   }
-  RegisterPathProvider();
   media::InitializeMediaLibrary();
   // When running in a child process for Mac sandbox tests, the sandbox exists
   // to initialize GL, so don't do it here.