[ServiceWorker] Don't send the UMA related headers to the ServiceWorker.

components/variations/net/variations_http_header_provider.cc

Index: components/variations/net/variations_http_header_provider.cc
diff --git a/components/variations/net/variations_http_header_provider.cc b/components/variations/net/variations_http_header_provider.cc
index 1220fae1640fc55545dfd978226b677ab3ebb0f3..0ce748aff038159a423cb11d85bd63df9120454f 100644
--- a/components/variations/net/variations_http_header_provider.cc
+++ b/components/variations/net/variations_http_header_provider.cc
@@ -14,6 +14,7 @@
 #include "base/strings/string_util.h"
 #include "components/google/core/browser/google_util.h"
 #include "components/variations/proto/client_variations.pb.h"
+#include "content/public/browser/service_worker_context.h"

[Alexei Svitkine (slow), 2014/10/27 15:09:00]

Hmm, I don't think we want to do this.

This code is in a component, partly because it's used by the iOS port of
Chromium. Which shouldn't depend on the content API.

 #include "net/base/registry_controlled_domains/registry_controlled_domain.h"
 #include "net/http/http_request_headers.h"
 #include "url/gurl.h"
@@ -36,6 +37,9 @@ const char* kSuffixesToSetHeadersFor[] = {
   ".ytimg.com",
 };
 
+const char kChromeUMAEnabled[] = "X-Chrome-UMA-Enabled";
+const char kClientData[] = "X-Client-Data";
+
 }  // namespace
 
 VariationsHttpHeaderProvider* VariationsHttpHeaderProvider::GetInstance() {
@@ -61,7 +65,7 @@ void VariationsHttpHeaderProvider::AppendHeaders(
     return;
 
   if (uma_enabled)
-    headers->SetHeaderIfMissing("X-Chrome-UMA-Enabled", "1");
+    headers->SetHeaderIfMissing(kChromeUMAEnabled, "1");
 
   // Lazily initialize the header, if not already done, before attempting to
   // transmit it.
@@ -75,8 +79,7 @@ void VariationsHttpHeaderProvider::AppendHeaders(
 
   if (!variation_ids_header_copy.empty()) {
     // Note that prior to M33 this header was named X-Chrome-Variations.
-    headers->SetHeaderIfMissing("X-Client-Data",
-                                variation_ids_header_copy);
+    headers->SetHeaderIfMissing(kClientData, variation_ids_header_copy);
   }
 }
 
@@ -113,6 +116,10 @@ bool VariationsHttpHeaderProvider::SetDefaultVariationIds(
 
 VariationsHttpHeaderProvider::VariationsHttpHeaderProvider()
     : variation_ids_cache_initialized_(false) {
+  content::ServiceWorkerContext::AddExcludedHeaderNameForFetchEvent(

[Alexei Svitkine (slow), 2014/10/27 15:09:00]

Since this code can't depend on content/ per my comment above, my suggestion is
to expose a getter from this class for the headers. Since this class is a
singleton, then some initialization code in chrome/browser can query that getter
and call the ServiceWorkerContext::AddExcludeHeaderNameForFetchEvent() on them.

[michaeln, 2014/10/27 21:50:26]

Sounds reasonable, maybe the ChromeResourceDispatcherHostDelegate could arrange
to do that initialization on the IO thread.

[horo, 2014/10/28 02:35:05]

Done.

+      kChromeUMAEnabled);
+  content::ServiceWorkerContext::AddExcludedHeaderNameForFetchEvent(
+      kClientData);
 }
 
 VariationsHttpHeaderProvider::~VariationsHttpHeaderProvider() {