Implemented observer callbacks so the style knows when the source’s attribution changes and the map knows when the style’s attribution changes. Also implemented a getter for a tile source’s attribution.
Fixes#2723.
This function can be called from different threads and was depending
on a global `std::string protocol` which can do heap allocations.
The first thread to use it would initialized it which is not exactly
safe, so this patch moves it to a `char *` that is just a pointer to
the data segment, so no races.
Valgrind detected it on #6431.
```
==9874== Conditional jump or move depends on uninitialised value(s)
==9874== at 0x4C307C2: __memcmp_sse4_1 (in /home/travis/build/mapbox/mapbox-gl-native/mason_packages/linux-x86_64/valgrind/latest/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==9874== by 0x79896E: mbgl::util::mapbox::isMapboxURL(std::string const&) (in /home/travis/build/mapbox/mapbox-gl-native/build/qt-linux-x86_64/Release/mbgl-test)
==9874== by 0x6DC756: mbgl::style::TileSourceImpl::parseTileJSON(std::string const&, std::string const&, mbgl::SourceType, unsigned short) (in /home/travis/build/mapbox/mapbox-gl-native/build/qt-linux-x86_64/Release/mbgl-test)
==9874== by 0x6DDA6A: std::_Function_handler<void (mbgl::Response), mbgl::style::TileSourceImpl::loadDescription(mbgl::FileSource&)::{lambda(mbgl::Response)#1}>::_M_invoke(std::_Any_data const&, mbgl::Response&&) (in /home/travis/build/mapbox/mapbox-gl-native/build/qt-linux-x86_64/Release/mbgl-test)
==9874== by 0x50BE80: std::_Function_handler<void (), mbgl::StubFileSource::StubFileSource()::{lambda()#1}>::_M_invoke(std::_Any_data const&) (in /home/travis/build/mapbox/mapbox-gl-native/build/qt-linux-x86_64/Release/mbgl-test)
==9874== by 0x70972A5: QMetaObject::activate(QObject*, int, int, void**) (in /usr/lib/x86_64-linux-gnu/libQt5Core.so.5.2.1)
==9874== by 0x70A3621: QTimer::timerEvent(QTimerEvent*) (in /usr/lib/x86_64-linux-gnu/libQt5Core.so.5.2.1)
==9874== by 0x7098053: QObject::event(QEvent*) (in /usr/lib/x86_64-linux-gnu/libQt5Core.so.5.2.1)
==9874== by 0x60CCC8B: QApplicationPrivate::notify_helper(QObject*, QEvent*) (in /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5.2.1)
==9874== by 0x60D1E55: QApplication::notify(QObject*, QEvent*) (in /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5.2.1)
==9874== by 0x706FC2C: QCoreApplication::notifyInternal(QObject*, QEvent*) (in /usr/lib/x86_64-linux-gnu/libQt5Core.so.5.2.1)
==9874== by 0x70BC1AC: QTimerInfoList::activateTimers() (in /usr/lib/x86_64-linux-gnu/libQt5Core.so.5.2.1)
==9874==
```
* [core, ios, android] Use `auto` value for properties with calculated defaults
* Fix render tests
* [core] Don't use depth test unless text is pitch-aligned to map.
* Bump mapbox-gl-test-suite
* TransformState pitch is already in radians
* Reduce setDepthSublayer calls
* Bump test suite
So far, we didn't properly disable layers that are outside the zoom range. This means that we rendered layers that should not have been rendered, albeit we didn't make any attempt to load tiles for those layers. However, when zooming in/out, existing tiles might already have been loaded in the source which continued to be rendered. In most cases they weren't actually visible because either the matrices weren't updated, or the clip IDs weren't set so that they would be "rendered" off-screen and clipped completely. In any case, we did way too much work.
* [android] - do not update marker while creating, add activity to prevent regression
* [core] - add asserts to incorrect usage of update and remove annotations api
* [android] - fix marker tests
