Feat(compiler-base-error): add default() to DiagnosticHandler.

[zong-zhe]

issue #115.

1. Does this PR affect any open issues?(Y/N) and add issue references (e.g. "fix #123", "re #123".):

• N
• Y

#115

2. What is the scope of this PR (e.g. component or file name):

compiler_base_error

3. Provide a description of the PR(e.g. more details, effects, motivations or doc link):

• Affects user behaviors
• Contains syntax changes
• Contains variable changes
• Contains experimental features
• Performance regression: Consumes more CPU
• Performance regression: Consumes more Memory
• Other

The new default method does not need to load the template file, which solves the problem that the template file path may not be found.

4. Are there any breaking changes?(Y/N) and describe the breaking changes(e.g. more details, motivations or doc link):

• N
• Y

5. Are there test cases for these changes?(Y/N) select and add more details, references or doc links:

• Unit test
• Integration test
• Benchmark (add benchmark stats below)
• Manual test (add detailed scripts or steps below)
• Other

6. Release note

Please refer to Release Notes Language Style Guide to write a quality release note.

None

[coveralls]

Pull Request Test Coverage Report for Build 3343439879

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage decreased (-29.3%) to 60.1%

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Totals
Change from base Build 3343377828:	-29.3%
Covered Lines:	20963
Relevant Lines:	34880

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💛 - Coveralls

[Peefy]

LGTM

[He1pa]

lgtm