browser changes v56

From https://github.com/CyanogenMod/android_packages_apps_Browser
   fc0a321..c6af828  cm-12.0    -> github/cm-12.0
Log an error when no activity is found to handle a URL.
Implement BrowserPreferencePage.isValidFragment.
Revert ""Browser: Update BrowserPreferencesPage to Override isValidFragment
Rewrite calls to Proxy.getPreferredHttpHost
Browser: fix crash updating recycled favicon
Browser: Fix Progress bar when quick Controls Enabled
browser: properly handle get center tab
BrowserSettings: update desktop UA string to match Chrome 37
Show a startup page in incognito mode
Implement client-side incognito mode
Browser: Fix browser force close
Add back browser history page.
Browser: fix weird behavior in the settings
Browser: added rtl support
Browser: Fix build warnings.
Add fullscreen toggle to menu
Adding exception handler for voice recognition activity
Support video transition animation
Browser: Add a more user friendly name for user agent
Browser: Update search engines
Browser: Increased tab limit
Browser : Open in incognito tab
Browser: New navbar buttons
Browser: UI updates