Introduce content::PageState (again).

android_webview/native/state_serializer.cc

Index: android_webview/native/state_serializer.cc
diff --git a/android_webview/native/state_serializer.cc b/android_webview/native/state_serializer.cc
index 656b2d03dec29e1257ef0e50c24462d1a9888740..5abc929320e989d6d03a19f0e05c5b8b687383d2 100644
--- a/android_webview/native/state_serializer.cc
+++ b/android_webview/native/state_serializer.cc
@@ -12,6 +12,7 @@
 #include "content/public/browser/navigation_controller.h"
 #include "content/public/browser/navigation_entry.h"
 #include "content/public/browser/web_contents.h"
+#include "content/public/common/page_state.h"
 
 // Reasons for not re-using TabNavigation under chrome/ as of 20121116:
 // * Android WebView has different requirements for fields to store since
@@ -146,7 +147,7 @@ bool WriteNavigationEntryToPickle(const content::NavigationEntry& entry,
   if (!pickle->WriteString16(entry.GetTitle()))
     return false;
 
-  if (!pickle->WriteString(entry.GetContentState()))
+  if (!pickle->WriteString(entry.GetPageState().ToEncodedData()))

[joth, 2013/05/28 22:04:34]

does the alter the format it is written out to the pickle as? If so, pleae could
you bump AW_STATE_VERSION => 20130528?

     return false;
 
   if (!pickle->WriteBool(static_cast<int>(entry.GetHasPostData())))
@@ -211,7 +212,8 @@ bool RestoreNavigationEntryFromPickle(PickleIterator* iterator,
     string content_state;
     if (!iterator->ReadString(&content_state))
       return false;
-    entry->SetContentState(content_state);
+    entry->SetPageState(
+        content::PageState::CreateFromEncodedData(content_state));

[joth, 2013/05/28 22:59:44]

latent question.... what if |content_state| is bogus and so the constructed
PageState::IsValid() will return false?
- I think we should detect it and bail out with a 'return false' here?
- That would mean the //DHCECK(IsValid()) you have commented out in the
PageState c'tor could never be enforced - least we make an untestable code path
here.
- Or we could have CreateFromPossiblyInvalidEndedData() factory method? hmm.

(Receiving bogus data here is plausible, if highly unlikely, as the state is
handed over to embedding app to persist and return to us.)

   }
 
   {