Assert in FrameView::paintContents

On this page :
http://serv24.jeu-a1.com/jeu-chequecadeaux.com/a95ab8b103856cb04f902641a6dc4581.html
when filling up the form and clicking on the button to validate informations, the application crash.

In debug mode, I have this message :

ASSERTION FAILED: !needsLayout()
page\FrameView.cpp(3595) : virtual void WebCore::FrameView::paintContents(WebCore::GraphicsContext*, const WebCore::IntRect&)
1 0D516FD4
2 0C2A5C86
3 0C268B3E
4 0C1F9D60
5 0C2298EA
6 0C2A307E
7 0D4C5581
8 0D4C5783
9 0D58F9A1
10 0D4398E4
11 0D4337DB
12 0D43312E
13 0D43D6FF
14 0D43C90B
15 0D43C95E
16 0D43C95E
17 0D43C95E
18 0D43C95E
19 0D43C95E
20 0C246CC9
21 0D607CC8
22 0D607CF9
23 0BE852B6
24 0E23EBC2
25 0D50658A
26 0D40111C
27 21D0E09F
28 21D0BB51
29 6B929DDE
30 6B9CF187
31 6B978CCF

This is my calls tree :

0 WTFCrash C:\Qt\5.3\mingw482_32\bin\Qt5WebKitd.dll 0xdc2fa85
1 WebCore::FrameView::paintContents(WebCore::GraphicsContext*, WebCore::IntRect const&) C:\Qt\5.3\mingw482_32\bin\Qt5WebKitd.dll 0xd608079
2 WebCore::ScrollView::paint(WebCore::GraphicsContext*, WebCore::IntRect const&) C:\Qt\5.3\mingw482_32\bin\Qt5WebKitd.dll 0xd516fd4
3 WebCore::RenderWidget::paintContents(WebCore::PaintInfo&, WebCore::LayoutPoint const&) C:\Qt\5.3\mingw482_32\bin\Qt5WebKitd.dll 0xc2a5c86
4 WebCore::RenderWidget::paint(WebCore::PaintInfo&, WebCore::LayoutPoint const&) C:\Qt\5.3\mingw482_32\bin\Qt5WebKitd.dll 0xc268b3e
5 WebCore::RenderLayer::paintForegroundForFragmentsWithPhase(WebCore::PaintPhase, WTF::Vector<WebCore::LayerFragment, 1u, WTF::CrashOnOverflow> const&, WebCore::GraphicsContext*, WebCore::RenderLayer::LayerPaintingInfo const&, unsigned int, WebCore::RenderObject*) C:\Qt\5.3\mingw482_32\bin\Qt5WebKitd.dll 0xc1f9d60
6 WebCore::RenderLayer::paintForegroundForFragments(WTF::Vector<WebCore::LayerFragment, 1u, WTF::CrashOnOverflow> const&, WebCore::GraphicsContext*, WebCore::GraphicsContext*, WebCore::LayoutRect const&, bool, WebCore::RenderLayer::LayerPaintingInfo const&, unsigned int, WebCore::RenderObject*, bool, bool) C:\Qt\5.3\mingw482_32\bin\Qt5WebKitd.dll 0xc2298ea
7 WebCore::RenderLayer::paintLayerContents(WebCore::GraphicsContext*, WebCore::RenderLayer::LayerPaintingInfo const&, unsigned int) C:\Qt\5.3\mingw482_32\bin\Qt5WebKitd.dll 0xc2a307e
8 WebCore::RenderLayerBacking::paintIntoLayer(WebCore::GraphicsLayer const*, WebCore::GraphicsContext*, WebCore::IntRect const&, unsigned int, unsigned int) C:\Qt\5.3\mingw482_32\bin\Qt5WebKitd.dll 0xd4c5581
9 WebCore::RenderLayerBacking::paintContents(WebCore::GraphicsLayer const*, WebCore::GraphicsContext&, unsigned int, WebCore::IntRect const&) C:\Qt\5.3\mingw482_32\bin\Qt5WebKitd.dll 0xd4c5783
10 WebCore::GraphicsLayer::paintGraphicsLayerContents(WebCore::GraphicsContext&, WebCore::IntRect const&) C:\Qt\5.3\mingw482_32\bin\Qt5WebKitd.dll 0xd58f9a1
11 WebCore::BitmapTextureImageBuffer::updateContents(WebCore::TextureMapper*, WebCore::GraphicsLayer*, WebCore::IntRect const&, WebCore::IntPoint const&, WebCore::BitmapTexture::UpdateContentsFlag) C:\Qt\5.3\mingw482_32\bin\Qt5WebKitd.dll 0xd4398e4
12 WebCore::TextureMapperTile::updateContents(WebCore::TextureMapper*, WebCore::GraphicsLayer*, WebCore::IntRect const&, WebCore::BitmapTexture::UpdateContentsFlag) C:\Qt\5.3\mingw482_32\bin\Qt5WebKitd.dll 0xd4337db
13 WebCore::TextureMapperTiledBackingStore::updateContents(WebCore::TextureMapper*, WebCore::GraphicsLayer*, WebCore::FloatSize const&, WebCore::IntRect const&, WebCore::BitmapTexture::UpdateContentsFlag) C:\Qt\5.3\mingw482_32\bin\Qt5WebKitd.dll 0xd43312e
14 WebCore::GraphicsLayerTextureMapper::updateBackingStoreIfNeeded() C:\Qt\5.3\mingw482_32\bin\Qt5WebKitd.dll 0xd43d6ff
15 WebCore::GraphicsLayerTextureMapper::flushCompositingState(WebCore::FloatRect const&) C:\Qt\5.3\mingw482_32\bin\Qt5WebKitd.dll 0xd43c90b
16 WebCore::GraphicsLayerTextureMapper::flushCompositingState(WebCore::FloatRect const&) C:\Qt\5.3\mingw482_32\bin\Qt5WebKitd.dll 0xd43c95e
17 WebCore::GraphicsLayerTextureMapper::flushCompositingState(WebCore::FloatRect const&) C:\Qt\5.3\mingw482_32\bin\Qt5WebKitd.dll 0xd43c95e
18 WebCore::GraphicsLayerTextureMapper::flushCompositingState(WebCore::FloatRect const&) C:\Qt\5.3\mingw482_32\bin\Qt5WebKitd.dll 0xd43c95e
19 WebCore::GraphicsLayerTextureMapper::flushCompositingState(WebCore::FloatRect const&) C:\Qt\5.3\mingw482_32\bin\Qt5WebKitd.dll 0xd43c95e
20 WebCore::GraphicsLayerTextureMapper::flushCompositingState(WebCore::FloatRect const&) C:\Qt\5.3\mingw482_32\bin\Qt5WebKitd.dll 0xd43c95e
21 WebCore::RenderLayerCompositor::flushPendingLayerChanges(bool) C:\Qt\5.3\mingw482_32\bin\Qt5WebKitd.dll 0xc246cc9
22 WebCore::FrameView::flushCompositingStateForThisFrame(WebCore::Frame*) C:\Qt\5.3\mingw482_32\bin\Qt5WebKitd.dll 0xd607cc8
23 WebCore::FrameView::flushCompositingStateIncludingSubframes() C:\Qt\5.3\mingw482_32\bin\Qt5WebKitd.dll 0xd607cf9
24 WebCore::TextureMapperLayerClientQt::syncLayers(WebCore::Timer<WebCore::TextureMapperLayerClientQt>*) C:\Qt\5.3\mingw482_32\bin\Qt5WebKitd.dll 0xbe852b6
25 WebCore::Timer<WebCore::TextureMapperLayerClientQt>::fired() C:\Qt\5.3\mingw482_32\bin\Qt5WebKitd.dll 0xe23ebc2
26 WebCore::ThreadTimers::sharedTimerFiredInternal() C:\Qt\5.3\mingw482_32\bin\Qt5WebKitd.dll 0xd50658a
27 WebCore::SharedTimerQt::timerEvent(QTimerEvent*) C:\Qt\5.3\mingw482_32\bin\Qt5WebKitd.dll 0xd40111c
28 QObject::event 1222 0x6b94f334
29 QApplicationPrivate::notify_helper 3522 0x21d0e09f
30 QApplication::notify 2975 0x21d0bb51
31 QCoreApplication::notifyInternal 935 0x6b929dde
32 QCoreApplication::sendEvent 237 0x6b9cf187
33 QEventDispatcherWin32Private::sendTimerEvent 585 0x6b978ccf
34 qt_internal_proc(HWND__*, unsigned int, unsigned int, long)@16 426 0x6b97859a
35 gapfnScSendMessage C:\Windows\syswow64\user32.dll 0x758262fa
36 ?? 0x201c2
37 USER32!GetThreadDesktop C:\Windows\syswow64\user32.dll 0x75826d3a
38 __lambda0::operator() 364 0x6b97828b
39 ?? 0x201c2
40 USER32!CharPrevW C:\Windows\syswow64\user32.dll 0x758277c4
41 USER32!DispatchMessageW C:\Windows\syswow64\user32.dll 0x7582788a
42 QEventDispatcherWin32::processEvents 756 0x6b979853
43 QWindowsGuiEventDispatcher::processEvents 80 0x6285cdc0
44 QEventLoop::processEvents 136 0x6b927e84
45 QEventLoop::exec 212 0x6b92811f
46 QCoreApplication::exec 1188 0x6b92a42d
47 QGuiApplication::exec 1450 0x3c862e2
48 QApplication::exec 2767 0x21d0b495
49 qMain main.cpp 120 0x454942
50 WinMain@16 131 0x4689ed
51 main 0x4884bd

Disassembler part :

Function: WTFCrash
0xdc2fa71 <+0x0001> in (%dx),%al
0xdc2fa72 <+0x0002> or $0xa1,%al
0xdc2fa74 <+0x0004> shrb $0x10,0x1a(%ecx)
0xdc2fa78 <+0x0008> test %eax,%eax
0xdc2fa7a <+0x000a> je 0xdc2fa7e <WTFCrash+14>
0xdc2fa7c <+0x000c> call *%eax
0xdc2fa7e <+0x000e> call 0xdc2fa10 <WTFReportBacktrace>
0xdc2fa83 <+0x0013> xor %eax,%eax
0xdc2fa85 <+0x0015> movl $0x0,0xbbadbeef
0xdc2fa8f <+0x001f> add $0xc,%esp
0xdc2fa92 <+0x0022> jmp *%eax
0xdc2fa94 <+0x0024> lea 0x0(%esi),%esi
0xdc2fa9a <+0x002a> lea 0x0(%edi),%edi
Function: vprintf_stderr_with_prefix
0xdc2faa0 push %ebp
0xdc2faa1 <+0x0001> mov %eax,%ebp
0xdc2faa3 <+0x0003> push %edi
0xdc2faa4 <+0x0004> mov %edx,%edi
0xdc2faa6 <+0x0006> push %esi
0xdc2faa7 <+0x0007> push %ebx
0xdc2faa8 <+0x0008> sub $0x2c,%esp
0xdc2faab <+0x000b> mov %eax,(%esp)
0xdc2faae <+0x000e> mov %ecx,0x14(%esp)
0xdc2fab2 <+0x0012> call 0xdc3ed40 <strlen>
0xdc2fab7 <+0x0017> mov %edi,(%esp)
0xdc2faba <+0x001a> mov %eax,%esi
0xdc2fabc <+0x001c> call 0xdc3ed40 <strlen>
0xdc2fac1 <+0x0021> lea (%eax,%esi,1),%edx
0xdc2fac4 <+0x0024> mov %eax,0x1c(%esp)
0xdc2fac8 <+0x0028> lea 0x1(%edx),%eax
0xdc2facb <+0x002b> mov %eax,(%esp)
0xdc2face <+0x002e> mov %edx,0x18(%esp)
0xdc2fad2 <+0x0032> call 0xdc31110 <_Znaj>
0xdc2fad7 <+0x0037> mov %esi,0x8(%esp)
0xdc2fadb <+0x003b> mov %ebp,0x4(%esp)
0xdc2fadf <+0x003f> mov %eax,(%esp)
0xdc2fae2 <+0x0042> mov %eax,%ebx
0xdc2fae4 <+0x0044> call 0xdc3ed48 <memcpy>