Expand use of type-safe BitFlags and enum class.

[kpschoedel]

Problem

• BitFlags.h has relatively unsafe deprecated functions.
• Some bit flags use enum rather than type-safe enum class.

Summary of Changes

• Removed deprecated SetFlags(), ClearFlags(), and GetFlags(),
  replacing uses with BitFlags.

• BitFlags.h changes:

  • Default to use std::underlying_type rather than requiring it as a template parameter.
  • Added BitFlags operations to reduce uses of type-unsafe Raw() and SetRaw():
    • Multi-argument constructors.
    • operator FlagsEnum().
    • ClearAll().
    • HasAny() and HasAll(), following the pattern of the existing HasOnly().
    • Binary &.

• Converted various bit flag types from enum to enum class:

  • BLEEndPoint::ConnectionStateFlags
  • BLEEndPoint::TimerStateFlags
  • BLEManagerImpl::Flags
  • Command::CommandPathFlags
  • Encoding::HexFlags
  • GenericConfigurationManagerImpl::Flags
  • GenericConnectivityManagerImpl_Thread::Flags
  • GenericConnectivityManagerImpl_WiFi::ConnectivityFlags
  • bdx::RangeControlFlags
  • bdx::StatusCode
  • bdx::TransferControlFlags
  • bdx::TransferRole

[andy31415]

Should we implement operator |= and | instead?

I find declaring BitFlags for single constants a bit odd:

// why would we need this:
static const BitFlags<CertValidateFlags> sIgnoreNotBeforeFlag(CertValidateFlags::kIgnoreNotBefore);
static const BitFlags<CertValidateFlags> sIgnoreNotAfterFlag(CertValidateFlags::kIgnoreNotAfter);

// when we can just use 
// CertValidateFlags::kIgnoreNotBefore
// CertValidateFlags::kIgnoreNotAfter)

directly

[kpschoedel]

Personally I agree, but this PR already exploded beyond what I thought it would be when I pulled on the loose string, so I drew the line at making the flag enums type-safe using the existing notation.

The TestChipCert usage does seems a bit strange. I assume the idea was to have shorter names to keep sValidationTestCases somewhat readable.

[kpschoedel]

Also, Clear would remain a bit ugly — flags &= ~BitFlags<FlagsType>(kFlagValue) — unless we define a free operator~ on enum classes.