Suppress -Wmissing-field-initializers warnings with GCC 4.9

[Csaba Osztrogonác]

There are many build failures with GCC 4.9, because this GCC version is buggy
and reports false positive warnings for empty initializer lists:

DerivedSources/WebCore/JSIDBObjectStore.cpp: In function 'T WebCore::convert(JSC::ExecState&, JSC::JSValue) [with T = WebCore::IDBObjectStore::IndexParameters]':
DerivedSources/WebCore/JSIDBObjectStore.cpp:55:18: error: missing initializer for member 'WebCore::IDBObjectStore::IndexParameters::unique' [-Werror=missing-field-initializers]
DerivedSources/WebCore/JSIDBObjectStore.cpp:55:18: error: missing initializer for member 'WebCore::IDBObjectStore::IndexParameters::multiEntry' [-Werror=missing-field-initializers]
DerivedSources/WebCore/JSIDBObjectStore.cpp:59:18: error: missing initializer for member 'WebCore::IDBObjectStore::IndexParameters::unique' [-Werror=missing-field-initializers]
DerivedSources/WebCore/JSIDBObjectStore.cpp:59:18: error: missing initializer for member 'WebCore::IDBObjectStore::IndexParameters::multiEntry' [-Werror=missing-field-initializers]
cc1plus: all warnings being treated as errors

DerivedSources/WebCore/JSFontFace.cpp: In function 'T WebCore::convert(JSC::ExecState&, JSC::JSValue) [with T = WebCore::FontFace::Descriptors]':
DerivedSources/WebCore/JSFontFace.cpp:100:18: error: missing initializer for member 'WebCore::FontFace::Descriptors::style' [-Werror=missing-field-initializers]
DerivedSources/WebCore/JSFontFace.cpp:100:18: error: missing initializer for member 'WebCore::FontFace::Descriptors::weight' [-Werror=missing-field-initializers]
...

DerivedSources/WebCore/JSElement.cpp: In function 'T WebCore::convert(JSC::ExecState&, JSC::JSValue) [with T = WebCore::Element::ShadowRootInit]':
DerivedSources/WebCore/JSElement.cpp:119:18: error: missing initializer for member 'WebCore::Element::ShadowRootInit::mode' [-Werror=missing-field-initializers]
cc1plus: all warnings being treated as errors

DerivedSources/WebCore/JSMutationObserver.cpp: In function 'T WebCore::convert(JSC::ExecState&, JSC::JSValue) [with T = WebCore::MutationObserver::Init]':
DerivedSources/WebCore/JSMutationObserver.cpp:47:18: error: missing initializer for member 'WebCore::MutationObserver::Init::childList' [-Werror=missing-field-initializers]
DerivedSources/WebCore/JSMutationObserver.cpp:47:18: error: missing initializer for member 'WebCore::MutationObserver::Init::attributes' [-Werror=missing-field-initializers]
...

I think the easiest way to fix these build failures is suppressing this warning with GCC 4.9

[Csaba Osztrogonác]

Created attachment 279380 [details]
Patch

[Csaba Osztrogonác]

forgot to mention the GCC bug report: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=36750

[Build Bot]

Comment on attachment 279380 [details]
Patch

Attachment 279380 [details] did not pass ios-sim-ews (ios-simulator-wk2):
Output: http://webkit-queues.webkit.org/results/1347827

New failing tests:
fast/scrolling/ios/scrollTo-at-page-load.html

[Build Bot]

Created attachment 279383 [details]
Archive of layout-test-results from ews122 for ios-simulator-wk2

The attached test failures were seen while running run-webkit-tests on the ios-sim-ews.
Bot: ews122  Port: ios-simulator-wk2  Platform: Mac OS X 10.11.4

[Csaba Osztrogonác]

Comment on attachment 279380 [details]
Patch

ios tester is flakey ...

[WebKit Commit Bot]

Comment on attachment 279380 [details]
Patch

Clearing flags on attachment: 279380

Committed r201247: <http://trac.webkit.org/changeset/201247>

[WebKit Commit Bot]

All reviewed patches have been landed.  Closing bug.