Reviewed by Dimitri Glazkov.

        Implement per-storage-area quotas for LocalStorage
        https://bugs.webkit.org/show_bug.cgi?id=29991

        I put 90% of the code in StorageMap since the decision to allow an update is
        closely tied to quota tracking.  The quota is set via a page's Settings class.
        Like with the local storage path and whether it's enabled, it's assumed that
        all pages in the same group will have the same settings.  The setting defaults
        to 5mb which is what the spec suggests, but it can easily be changed to
        anything else--including StorageMap::noQuota.  Any values in LocalStorage are
        grandfathered in regarudless of quota, so importItem only tracks (and will
        never block) imports.

        I believe this change is a good transition to more complex quota management.
        For example, if we wanted to track quotas in the SQLite DB, then we'd just add
        a function to the StorageMap that sets the quota.  This would be fine since all
        use of LocalStorage is blocked on the import completing, so you'd never hit a
        quota error in the mean time.  Also, if embedders wanted to ask the user
        whether to expand the quota whenever it's hit (before deciding whether or not
        to raise an exception), a callback via the chrome client should be fairly easy.
        That said, I think it's best to add these features in steps rather than one
        huge patch.  (Both of these are on my TODO list, btw.)

        Included is a layout test that verifies the behavior.  It assumes the default
        quota is 5mb (since that's what Settings defaults to).

        Test: storage/domstorage/localstorage/quota.html

        * page/PageGroup.cpp:
        (WebCore::PageGroup::localStorage):
        * page/Settings.cpp:
        (WebCore::Settings::Settings):
        (WebCore::Settings::setLocalStorageQuota):
        * page/Settings.h:
        (WebCore::Settings::localStorageQuota):
        * storage/StorageAreaImpl.cpp:
        (WebCore::StorageAreaImpl::create):
        (WebCore::StorageAreaImpl::StorageAreaImpl):
        (WebCore::StorageAreaImpl::setItem):
        (WebCore::StorageAreaImpl::clear):
        * storage/StorageAreaImpl.h:
        * storage/StorageMap.cpp:
        (WebCore::StorageMap::create):
        (WebCore::StorageMap::StorageMap):
        (WebCore::StorageMap::copy):
        (WebCore::StorageMap::setItem):
        (WebCore::StorageMap::removeItem):
        (WebCore::StorageMap::importItem):
        * storage/StorageMap.h:
        (WebCore::StorageMap::quota):
        * storage/StorageNamespace.cpp:
        (WebCore::StorageNamespace::localStorageNamespace):
        * storage/StorageNamespace.h:
        * storage/StorageNamespaceImpl.cpp:
        (WebCore::StorageNamespaceImpl::localStorageNamespace):
        (WebCore::StorageNamespaceImpl::sessionStorageNamespace):
        (WebCore::StorageNamespaceImpl::StorageNamespaceImpl):
        (WebCore::StorageNamespaceImpl::copy):
        (WebCore::StorageNamespaceImpl::storageArea):
        * storage/StorageNamespaceImpl.h:
2009-10-02  Jeremy Orlow  <jorlow@chromium.org>

        Reviewed by Dimitri Glazkov.

        Implement per-storage-area quotas for LocalStorage
        https://bugs.webkit.org/show_bug.cgi?id=29991

        I put 90% of the code in StorageMap since the decision to allow an update is
        closely tied to quota tracking.  The quota is set via a page's Settings class. 
        Like with the local storage path and whether it's enabled, it's assumed that
        all pages in the same group will have the same settings.  The setting defaults
        to 5mb which is what the spec suggests, but it can easily be changed to
        anything else--including StorageMap::noQuota.  Any values in LocalStorage are
        grandfathered in regarudless of quota, so importItem only tracks (and will
        never block) imports.

        I believe this change is a good transition to more complex quota management. 
        For example, if we wanted to track quotas in the SQLite DB, then we'd just add
        a function to the StorageMap that sets the quota.  This would be fine since all
        use of LocalStorage is blocked on the import completing, so you'd never hit a
        quota error in the mean time.  Also, if embedders wanted to ask the user
        whether to expand the quota whenever it's hit (before deciding whether or not
        to raise an exception), a callback via the chrome client should be fairly easy.
        That said, I think it's best to add these features in steps rather than one
        huge patch.  (Both of these are on my TODO list, btw.)

        Included is a layout test that verifies the behavior.  It assumes the default
        quota is 5mb (since that's what Settings defaults to).

        * storage/domstorage/localstorage/quota-expected.txt: Added.
        * storage/domstorage/localstorage/quota.html: Added.
        * storage/domstorage/script-tests/quota.js: Added.
        (runTest):


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@49040 268f45cc-cd09-0410-ab3c-d52691b4dbfc