Web Inspector: InspectorFrontendHost.append has to be implemented for saving heap...

Web Inspector: InspectorFrontendHost.append has to be implemented for saving heap snapshots.
https://bugs.webkit.org/show_bug.cgi?id=85137

We can save a file with help of InspectorFrontendHost.save method,
but it is suitable only for relatively small portions of data and
can't process the 6Gb heap snapshot.
These methods just pass the url and content into embedder.

Reviewed by Yury Semikhatsky.

Source/WebCore:

* inspector/InspectorFrontendClient.h:
(InspectorFrontendClient):
* inspector/InspectorFrontendClientLocal.h:
(WebCore::InspectorFrontendClientLocal::append):
* inspector/InspectorFrontendHost.cpp:
(WebCore::InspectorFrontendHost::append):
(WebCore):
* inspector/InspectorFrontendHost.h:
(InspectorFrontendHost):
* inspector/InspectorFrontendHost.idl:

Source/WebKit/chromium:

* public/WebDevToolsFrontendClient.h:
(WebKit::WebDevToolsFrontendClient::append):
* src/InspectorFrontendClientImpl.cpp:
(WebKit::InspectorFrontendClientImpl::append):
(WebKit):
* src/InspectorFrontendClientImpl.h:
(InspectorFrontendClientImpl):

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@115577 268f45cc-cd09-0410-ab3c-d52691b4dbfc