Simplify WatchpointSet state tracking
https://bugs.webkit.org/show_bug.cgi?id=124465

Reviewed by Sam Weinig.
        
We previously represented the state of watchpoint sets using two booleans. But that
makes it awkward to case over the state.
        
We also previously supported a watchpoint set being both watched and invalidated. We
never used that capability, and its presence was just purely confusing.
        
This turns the whole thing into an enum.

* assembler/MacroAssemblerARM64.h:
(JSC::MacroAssemblerARM64::branch8):
* assembler/MacroAssemblerARMv7.h:
(JSC::MacroAssemblerARMv7::branch8):
* assembler/MacroAssemblerX86.h:
(JSC::MacroAssemblerX86::branch8):
* assembler/MacroAssemblerX86_64.h:
(JSC::MacroAssemblerX86_64::branch8):
* bytecode/Watchpoint.cpp:
(JSC::WatchpointSet::WatchpointSet):
(JSC::WatchpointSet::add):
(JSC::WatchpointSet::notifyWriteSlow):
(JSC::InlineWatchpointSet::inflateSlow):
* bytecode/Watchpoint.h:
(JSC::WatchpointSet::state):
(JSC::WatchpointSet::isStillValid):
(JSC::WatchpointSet::startWatching):
(JSC::WatchpointSet::notifyWrite):
(JSC::WatchpointSet::addressOfState):
(JSC::InlineWatchpointSet::InlineWatchpointSet):
(JSC::InlineWatchpointSet::hasBeenInvalidated):
(JSC::InlineWatchpointSet::startWatching):
(JSC::InlineWatchpointSet::notifyWrite):
(JSC::InlineWatchpointSet::decodeState):
(JSC::InlineWatchpointSet::encodeState):
* jit/JITPropertyAccess.cpp:
(JSC::JIT::emitVarInjectionCheck):
* jit/JITPropertyAccess32_64.cpp:
(JSC::JIT::emitVarInjectionCheck):
* llint/LowLevelInterpreter.asm:
* llint/LowLevelInterpreter32_64.asm:
* llint/LowLevelInterpreter64.asm:
* runtime/JSFunction.cpp:
(JSC::JSFunction::JSFunction):
* runtime/JSFunctionInlines.h:
(JSC::JSFunction::JSFunction):
* runtime/JSGlobalObject.cpp:
(JSC::JSGlobalObject::JSGlobalObject):
* runtime/Structure.cpp:
(JSC::Structure::Structure):
* runtime/SymbolTable.cpp:
(JSC::SymbolTableEntry::attemptToWatch):
* runtime/SymbolTable.h:



git-svn-id: http://svn.webkit.org/repository/webkit/trunk@159395 268f45cc-cd09-0410-ab3c-d52691b4dbfc