Hook up ProfileIOData's URLRequestContext to a NetworkService.

content/public/browser/content_browser_client.h

Index: content/public/browser/content_browser_client.h
diff --git a/content/public/browser/content_browser_client.h b/content/public/browser/content_browser_client.h
index 41cd656e552d09afa091b32e43211fe06d77b8e2..5f22c9e00285a050ca3a0ed1dc44935b63907b96 100644
--- a/content/public/browser/content_browser_client.h
+++ b/content/public/browser/content_browser_client.h
@@ -22,6 +22,7 @@
 #include "content/public/common/associated_interface_registry.h"
 #include "content/public/common/content_client.h"
 #include "content/public/common/media_stream_request.h"
+#include "content/public/common/network_service.mojom.h"
 #include "content/public/common/resource_type.h"
 #include "content/public/common/sandbox_type.h"
 #include "content/public/common/socket_permission_request.h"
@@ -143,6 +144,10 @@ struct OpenURLParams;
 struct Referrer;
 struct WebPreferences;
 
+namespace mojom {
+class NetworkContext;
+}
+
 // Embedder API (or SPI) for participating in browser logic, to be implemented
 // by the client of the content browser. See ChromeContentBrowserClient for the
 // principal implementation. The methods are assumed to be called on the UI
@@ -822,6 +827,18 @@ class CONTENT_EXPORT ContentBrowserClient {
   // This is called on the IO thread.
   virtual std::vector<std::unique_ptr<URLLoaderThrottle>>
   CreateURLLoaderThrottles(const base::Callback<WebContents*()>& wc_getter);
+
+  // Creates the main NetworkContext for a BrowserContext. It's called only once
+  // for a given BrowserContext.
+  virtual mojom::NetworkContextPtr CreateMainNetworkContext(
+      BrowserContext* context);
+
+  // Creates the main NetworkContext for a BrowserContext's StoragePartition. It

[jam, 2017/07/18 20:26:27]

I'm having trouble seeing these two methods descriptions and understanding the
difference. Would it be enough to have one method that takes in the file path?
The callers could then concatenate the relative + profile path.

[mmenke, 2017/07/18 20:57:34]

I'm not sufficiently familiar with StoragePartitions to know if that's enough. 
I'll combine them for now, and we can separate them if needed.

+  // can be called multiple times for a given BrowserContext.
+  virtual mojom::NetworkContextPtr CreateNetworkContextForStoragePartition(
+      BrowserContext* context,
+      bool in_memory,
+      const base::FilePath& partition_path);
 };
 
 }  // namespace content