Safebrowsing: change gethash caching to match api 2.3 rules, fix some corner cases.

chrome/browser/safe_browsing/safe_browsing_util.h

Index: chrome/browser/safe_browsing/safe_browsing_util.h
diff --git a/chrome/browser/safe_browsing/safe_browsing_util.h b/chrome/browser/safe_browsing/safe_browsing_util.h
index 783369ec35168531ea4e6a5878f418634654d478..a4fb0e85df167286b986057100cbe40b259159ff 100644
--- a/chrome/browser/safe_browsing/safe_browsing_util.h
+++ b/chrome/browser/safe_browsing/safe_browsing_util.h
@@ -15,6 +15,7 @@
 
 #include "base/basictypes.h"
 #include "base/strings/string_piece.h"
+#include "base/time/time.h"
 #include "chrome/browser/safe_browsing/chunk_range.h"
 
 class GURL;
@@ -40,6 +41,10 @@ inline bool SBFullHashEqual(const SBFullHash& a, const SBFullHash& b) {
   return !memcmp(a.full_hash, b.full_hash, sizeof(a.full_hash));
 }
 
+inline bool SBFullHashLess(const SBFullHash& a, const SBFullHash& b) {
+  return memcmp(a.full_hash, b.full_hash, sizeof(a.full_hash)) < 0;
+}
+
 // Generate full hash for the given string.
 SBFullHash SBFullHashForString(const base::StringPiece& str);
 
@@ -106,7 +111,15 @@ class SBChunkList {
 struct SBFullHashResult {
   SBFullHash hash;
   std::string list_name;
-  int add_chunk_id;
+};
+
+struct SBCachedFullHashResult {
+  SBCachedFullHashResult();
+  explicit SBCachedFullHashResult(const base::Time& in_expire_after);
+  ~SBCachedFullHashResult();
+
+  base::Time expire_after;
+  std::vector<SBFullHashResult> full_hashes;
 };
 
 // Contains information about a list in the database.