Add Reload and LoadData methods to WebFrame.

Add Reload and LoadData methods to WebFrame.  LoadData replaces
LoadAlternateHTMLString, changing types to WebKit API types and
allowing for more flexibility (supports loading non-HTML data).

LoadHTMLString is modified to support some optional parameters.

Note: Since WebFrame is going to soon be part of the WebKit API,
it is OK style-wise for it to use optional parameters.

This patch also includes a change to remove the securityInfo
property from WebURLRequest.  I did this so that I could eliminate
the need to pass a WebURLRequest to LoadData / LoadHTMLString.
This also fixes a TODO of mine to eliminate this field on
WebCore::ResourceRequest since securityInfo (SSL cert info) is
really more of a response property.  It was only part of the
request as a hack to support certain error pages.  I work around
that by leveraging NavigationState in chrome/renderer.

I added some templatized, implicit constructors to WebData for
convenience.  I plan to make similar changes to WebCString and
WebString in a future CL.

This CL is a incremental step toward moving ResourceFetcher out
of WebFrame.

BUG=15648
TEST=none
R=dglazkov


Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=19742

[dglazkov, 2009-07-01 17:09:27]

LGTM!