initial add of SQL based storage

components/offline_pages/BUILD.gn

Index: components/offline_pages/BUILD.gn
diff --git a/components/offline_pages/BUILD.gn b/components/offline_pages/BUILD.gn
index 84a6601ba7e1e7fff0cc6685c358ba37896bed1c..4a03e7955ea3764ce4e159f87e51887e10488c8d 100644
--- a/components/offline_pages/BUILD.gn
+++ b/components/offline_pages/BUILD.gn
@@ -18,6 +18,8 @@ static_library("offline_pages") {
     "offline_page_metadata_store.h",
     "offline_page_metadata_store_impl.cc",
     "offline_page_metadata_store_impl.h",
+    "offline_page_metadata_store_sql.cc",
+    "offline_page_metadata_store_sql.h",
     "offline_page_model.cc",
     "offline_page_model.h",
   ]
@@ -30,6 +32,7 @@ static_library("offline_pages") {
     "//components/leveldb_proto",
     "//components/offline_pages/proto:offline_pages_proto",
     "//net",
+    "//sql",
     "//third_party/leveldatabase",
     "//url",
   ]
@@ -84,6 +87,7 @@ source_set("unit_tests") {
     "//components/bookmarks/test",
     "//components/leveldb_proto",
     "//components/offline_pages/proto:offline_pages_proto",
+    "//sql:sql",

[Scott Hess - ex-Googler, 2016/04/25 19:57:55]

Why is this //sql:sql while the other was //sql?

[bburns, 2016/04/26 23:27:02]

good question, changed the other to sql:sql (they're equivalent, but the
consistency is good, I suppose)

[Scott Hess - ex-Googler, 2016/04/27 15:21:00]

In that case ... why //sql:sql but not //url:url?

[I still can't figure out if this little voice in my head is a defect or not!]

[bburns, 2016/04/27 19:59:21]

if you do "//foo" it implicitly means "//foo:foo"

so I guess it's a style thing, I'm not sure there is a ton of consistency around
this, but I don't super care.

[Scott Hess - ex-Googler, 2016/04/27 21:16:45]

I'm fine with a "don't care", mostly I was pointing it out because the case
you're adding is the only case in this file where it's //x:x.

     "//testing/gtest",
     "//url",
   ]