Bug 1006485 - Part a: Rename FileHandle to MutableFile and LockedFile to FileHandle; r=bent

--HG--
rename : dom/filehandle/FileHandle.cpp => dom/filehandle/MutableFile.cpp
rename : dom/filehandle/FileHandle.h => dom/filehandle/MutableFile.h
rename : dom/filehandle/test/test_lockedfile_lifetimes.html => dom/filehandle/test/test_filehandle_lifetimes.html
rename : dom/filehandle/test/test_lockedfile_lifetimes_nested.html => dom/filehandle/test/test_filehandle_lifetimes_nested.html
rename : dom/filehandle/test/test_lockedfile_ordering.html => dom/filehandle/test/test_filehandle_ordering.html
rename : dom/filehandle/test/test_overlapping_lockedfiles.html => dom/filehandle/test/test_overlapping_filehandles.html
rename : dom/filehandle/test/test_readonly_lockedfiles.html => dom/filehandle/test/test_readonly_filehandles.html
rename : dom/indexedDB/IDBFileHandle.cpp => dom/indexedDB/IDBMutableFile.cpp
rename : dom/indexedDB/IDBFileHandle.h => dom/indexedDB/IDBMutableFile.h
rename : dom/webidl/IDBFileHandle.webidl => dom/webidl/IDBMutableFile.webidl
rename : dom/webidl/FileHandle.webidl => dom/webidl/MutableFile.webidl
Bug 1006485 - Part b: hg rename LockedFile.h/cpp/webidl in a separate patch for better readability; r=bent

--HG--
rename : dom/filehandle/LockedFile.cpp => dom/filehandle/FileHandle.cpp
rename : dom/filehandle/LockedFile.h => dom/filehandle/FileHandle.h
rename : dom/webidl/LockedFile.webidl => dom/webidl/FileHandle.webidl