Bug 936100 part 1: Adjust reftests and crashtests to no longer bother with flexbox pref. r=mats
Bug 936100 part 2: Adjust non-flexbox-specific mochitests to no longer bother with flexbox pref. r=mats
Bug 936100 part 3: Remove pref-setting mochitest wrappers for flexbox-specific mochitests, and transfer their boilerplate into the actual test files (currently named "file_"). r=mats
Bug 936100 part 4: Rename file_flexbox* mochitests (which were previously loaded in iframes) to test_flexbox*. r=mats

--HG--
rename : layout/style/test/file_flexbox_align_self_auto.html => layout/style/test/test_flexbox_align_self_auto.html
rename : layout/style/test/file_flexbox_child_display_values.xhtml => layout/style/test/test_flexbox_child_display_values.xhtml
rename : layout/style/test/file_flexbox_flex_grow_and_shrink.html => layout/style/test/test_flexbox_flex_grow_and_shrink.html
rename : layout/style/test/file_flexbox_flex_shorthand.html => layout/style/test/test_flexbox_flex_shorthand.html
rename : layout/style/test/file_flexbox_layout.html => layout/style/test/test_flexbox_layout.html
rename : layout/style/test/file_flexbox_order.html => layout/style/test/test_flexbox_order.html
rename : layout/style/test/file_flexbox_order_table.html => layout/style/test/test_flexbox_order_table.html
Bug 936100 part 5: Remove usage of flexbox pref from C++ code. r=mats
Bug 936100 part 6: Remove flexbox pref from all.js. r=mats