WebViewCore::createPrerenderCanvas failed unexpectedly

m_scrollSetTime not in WebViewCore's ctor makes it randomly
initialized, which leads to spurious scroll when creating
prerender in WebViewCore::createPrerenderCanvas, which hence
fails the creation.

Fix it by adding m_scrollSetTime in initialization list.

Change-Id: I4d834cfae091f645ac9cb4c99a4394164772872c
Signed-off-by: Yuyang Du <yuyang.du@intel.com>
Signed-off-by: Jack Ren <jack.ren@intel.com>
Signed-off-by: Beare, Bruce J <bruce.j.beare@intel.com>
Signed-off-by: Yuyang Du <yuyang.du@intel.com>
WebViewCore destructor must delete m_textFieldInitDataGlue

There was a memory leak detected in processes using webkit.
Investigation showed that it was the TextFieldInitDataGlue
object created in WebViewCore constructor.

Change-Id: I86a11f99f13aca6ab990627a9106c9e9b781edee
Fix leak of inspectorClient when INSPECTOR disabled

WebKit PageClient api has undefined memory management. It seems
to take custody of the parameters only if it wants to use it.
Thus, only allocate inspectorClient if needed.

Change-Id: Ibae7e683ec0c9553845c482b52dab7fad94e4398