Storage related test improvements and small fixes

[SeppoTakalo]

Description

Summary of change

Small changes in this PR:

• BufferedBlockDevice: Sync all the buffers on deinit()
• Don't allow over-read on BufferedBlockDevice
• HeapBlockDevice: Don't assert on const functions
• Remove unceressary NULL check from BufferedBlockDevice::size()
• SlicingBlockDevice should assert, if size does not look valid <-- IS THIS API CHANGE?
• Extend SlicingBlockDevice test coverage
• Greenteatests: Validate KVStore content when WRITE_ONCE flag is set.
• Remove flaky error_inject_test
• Fix Greentea handler typecasting

Documentation

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Pull request type

[] Patch update (Bug fix / Target update / Docs update / Test update / Refactor)
[X] Feature update (New feature / Functionality change / New API)
[] Major update (Breaking change E.g. Return code change / API behaviour change)

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Test results

[] No Tests required for this change (E.g docs only update)
[X] Covered by existing mbed-os tests (Greentea or Unittest)
[] Tests / results supplied as part of this PR

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Reviewers

@VeijoPesonen

Release Notes

Summary of changes

SlicingBlockDevice does not anymore accept both parameters as zero, or size as zero. SlicingBlockDevice(block, 0,0) used to create a block device that took up the whole block device. There is no sense on doing so, and if used like this, it has most probably been a programming error. Therefore the constructor now does MBED_ASSERT() if both parameters, start and stop point to same value. Effectively this prevents creating a slice that has size of zero, or take the full block device.

Impact of changes

You cannot anymore create a SlicingBlockDevice that has size of zero, or take the full size of underlying block device.

Migration actions required

No migration required for code that uses SlicingBlockDevice as it is intended.

[VeijoPesonen]

Looks good to me

[ciarmcom]

@SeppoTakalo, thank you for your changes.
@VeijoPesonen @ARMmbed/mbed-os-storage @ARMmbed/mbed-os-maintainers please review.

[VeijoPesonen]

Looks good to me

[mbed-ci]

Test run: FAILED

Summary: 1 of 11 test jobs failed
Build number : 1
Build artifacts

Failed test jobs:

• jenkins-ci/mbed-os-ci_greentea-test

[0xc0170]

Failures look related, please review

[SeppoTakalo]

Issue was that bcaf37d causes test to ASSERT if SlicingBlockDevice size is not valid.
This was fixed on kvstore_phase_1 test on abbb248 but not on "Phase_2"

Added a commit that fixes kvstore_phase_2 test as well.

[SeppoTakalo]

Started a CI.

[mbed-ci]

Test run: SUCCESS

Summary: 11 of 11 test jobs passed
Build number : 2
Build artifacts

[SeppoTakalo]

@0xc0170 This is ready.