[HttpCache] Store some memcache info to memory dumps for debugging

base/trace_event/memory_infra_background_whitelist.cc

Index: base/trace_event/memory_infra_background_whitelist.cc
diff --git a/base/trace_event/memory_infra_background_whitelist.cc b/base/trace_event/memory_infra_background_whitelist.cc
index 8f94f25a6dfb237681080e4a234fd5f1692e3f5c..746068a7b1edf227af4153b16b6783b98378658e 100644
--- a/base/trace_event/memory_infra_background_whitelist.cc
+++ b/base/trace_event/memory_infra_background_whitelist.cc
@@ -73,46 +73,64 @@ const char* const kAllocatorDumpNameWhitelist[] = {
     "net/url_request_context/app_request",
     "net/url_request_context/app_request/0x?",
     "net/url_request_context/app_request/0x?/http_cache",
+    "net/url_request_context/app_request/0x?/http_cache/memory_backend",
+    "net/url_request_context/app_request/0x?/http_cache/simple_backend",
     "net/url_request_context/app_request/0x?/http_network_session",
     "net/url_request_context/app_request/0x?/sdch_manager",
     "net/url_request_context/extensions",
     "net/url_request_context/extensions/0x?",
     "net/url_request_context/extensions/0x?/http_cache",
+    "net/url_request_context/extensions/0x?/http_cache/memory_backend",
+    "net/url_request_context/extensions/0x?/http_cache/simple_backend",
     "net/url_request_context/extensions/0x?/http_network_session",
     "net/url_request_context/extensions/0x?/sdch_manager",
     "net/url_request_context/isolated_media",
     "net/url_request_context/isolated_media/0x?",
     "net/url_request_context/isolated_media/0x?/http_cache",
+    "net/url_request_context/isolated_media/0x?/http_cache/memory_backend",
+    "net/url_request_context/isolated_media/0x?/http_cache/simple_backend",
     "net/url_request_context/isolated_media/0x?/http_network_session",
     "net/url_request_context/isolated_media/0x?/sdch_manager",
     "net/url_request_context/main",
     "net/url_request_context/main/0x?",
     "net/url_request_context/main/0x?/http_cache",
+    "net/url_request_context/main/0x?/http_cache/memory_backend",
+    "net/url_request_context/main/0x?/http_cache/simple_backend",
     "net/url_request_context/main/0x?/http_network_session",
     "net/url_request_context/main/0x?/sdch_manager",
     "net/url_request_context/main_media",
     "net/url_request_context/main_media/0x?",
     "net/url_request_context/main_media/0x?/http_cache",
+    "net/url_request_context/main_media/0x?/http_cache/memory_backend",
+    "net/url_request_context/main_media/0x?/http_cache/simple_backend",
     "net/url_request_context/main_media/0x?/http_network_session",
     "net/url_request_context/main_media/0x?/sdch_manager",
     "net/url_request_context/proxy",
     "net/url_request_context/proxy/0x?",
     "net/url_request_context/proxy/0x?/http_cache",
+    "net/url_request_context/proxy/0x?/http_cache/memory_backend",
+    "net/url_request_context/proxy/0x?/http_cache/simple_backend",
     "net/url_request_context/proxy/0x?/http_network_session",
     "net/url_request_context/proxy/0x?/sdch_manager",
     "net/url_request_context/safe_browsing",
     "net/url_request_context/safe_browsing/0x?",
     "net/url_request_context/safe_browsing/0x?/http_cache",
+    "net/url_request_context/safe_browsing/0x?/http_cache/memory_backend",
+    "net/url_request_context/safe_browsing/0x?/http_cache/simple_backend",
     "net/url_request_context/safe_browsing/0x?/http_network_session",
     "net/url_request_context/safe_browsing/0x?/sdch_manager",
     "net/url_request_context/system",
     "net/url_request_context/system/0x?",
     "net/url_request_context/system/0x?/http_cache",
+    "net/url_request_context/system/0x?/http_cache/memory_backend",
+    "net/url_request_context/system/0x?/http_cache/simple_backend",
     "net/url_request_context/system/0x?/http_network_session",
     "net/url_request_context/system/0x?/sdch_manager",
     "net/url_request_context/unknown",
     "net/url_request_context/unknown/0x?",
     "net/url_request_context/unknown/0x?/http_cache",
+    "net/url_request_context/unknown/0x?/http_cache/memory_backend",
+    "net/url_request_context/unknown/0x?/http_cache/simple_backend",
     "net/url_request_context/unknown/0x?/http_network_session",
     "net/url_request_context/unknown/0x?/sdch_manager",
     "web_cache/Image_resources",