This ensures that non-breaking space chars (not HTML entities) are
removed from text obtainined from the composer, and moves the F=F text
formatting from JS back to Vala, to minimimse the JS footprint and return
to using the old (working) version again.
* src/client/composer/composer-web-view.vala (ClientWebView::get_text):
Restore the old F=F formatting code previously in webkit-util, apply it
to plain text obtained from the composer.
* test/client/components/client-web-view-test-case.vala: New base class
for tests involving ClientWebView.
* test/client/composer/composer-web-view-test.vala: New tests for
ComposerWebView::get_html and ::get_text.
* test/js/composer-page-state-test.vala: Reworked to use
ClientWebViewTestCase, updated tests now that JS is returning
QUOTE_MARKER-delinated text, not F=F text.
* test/testcase.vala (TestCase): Move ::async_complete and ::async_result
from ComposerPageStateTest so all test cases can test async code.
* test/CMakeLists.txt: Add new source files.
* test/main.vala (main): Add new test.
* ui/composer-web-view.js: Update doc comments, remove F=F code, break
out non-breaking space replacement so it can be tested.