Do not bring up the soft keyboard for readonly input fields.

Partial fix for http://b/issue?id=2159869.  Add a field to CachedNode
for readonly.  In WebView.cpp, only call displaySoftKeyboard if the
node is not readonly.  Also call displaySoftKeyboard in nativeTextMotionUp
to replace a call being removed in WebView.touchUpOnTextField(java).
3 files changed