Remove suppressions for WebKit Linux bot as it is gone.

tools/valgrind/memcheck/suppressions.txt

 # There are four kinds of suppressions in this file.
 # 1. third party stuff we have no control over
 #
 # 2. intentional unit test errors, or stuff that is somehow a false positive
 # in our own code, or stuff that is so trivial it's not worth fixing
 #
 # 3. Suppressions for real chromium bugs that are not yet fixed.
 # These should all be in chromium's bug tracking system (but a few aren't yet).
 # Periodically we should sweep this file and the bug tracker clean by
 # running overnight and removing outdated bugs/suppressions.
@@ skipping 1817 matching lines @@
    fun:_ZN11dom_storage22SessionStorageDatabase24ReadNamespacesAndOriginsEPSt3mapISsSt6vectorI4GURLSaIS3_EESt4lessISsESaISt4pairIKSsS5_EEE
    fun:_ZN11dom_storage17DomStorageContext36FindUnusedNamespacesInCommitSequenceERKSt3setISsSt4lessISsESaISsEES7_
 }
 {
    bug_175823
    Memcheck:Leak
    ...
    fun:_ZN18ValueStoreFrontend*
 }
 {
-   bug_176616_a
-   Memcheck:Uninitialized
-   fun:_ZN13WebTestRunner16WebTestProxyBase19didCreateDataSourceEPN5blink8WebFrameEPNS1_13WebDataSourceE
-   fun:_ZN13WebTestRunner12WebTestProxyI11WebViewHostP9TestShellE19didCreateDataSourceEPN5blink8WebFrameEPNS5_13WebDataSourceE
-   fun:_ZN5blink21FrameLoaderClientImpl20createDocumentLoaderERKN7blink15ResourceRequestERKNS1_14SubstituteDataE
-   fun:_ZN5blink11FrameLoader4initEv
-   fun:_ZN5blink5Frame4initEv
-   fun:_ZN5blink12WebFrameImpl21initializeAsMainFrameEPN7blink4PageE
-   fun:_ZN5blink11WebViewImpl19initializeMainFrameEPNS_14WebFrameClientE
-   fun:_ZN9TestShell15createNewWindowERKN5blink6WebURLEP16DRTDevToolsAgentPN13WebTestRunner17WebTestInterfacesE
-   fun:_ZN9TestShell16createMainWindowEv
-   fun:_ZN9TestShell10initializeEP25MockWebKitPlatformSupport
-}
-{
-   bug_176616_b
-   Memcheck:Uninitialized
-   fun:_ZN13WebTestRunner10TestRunner5resetEv
-   fun:_ZN13WebTestRunner14TestInterfaces8resetAllEv
-   fun:_ZN13WebTestRunner17WebTestInterfaces8resetAllEv
-   fun:_ZN9TestShell19resetTestControllerEv
-   fun:_ZL7runTestR9TestShellR10TestParamsRKSsb
-}
-{
    bug_176619_a
    Memcheck:Uninitialized
    fun:_ZN3WTF6StringC1EPKt
    fun:_ZN5blink12WebVTTParser22constructTreeFromTokenEPNS_8DocumentE
    fun:_ZN5blink12WebVTTParser33createDocumentFragmentFromCueTextERKN3WTF6StringE
    fun:_ZN5blink12TextTrackCue20createWebVTTNodeTreeEv
    fun:_ZN5blink12TextTrackCue22createCueRenderingTreeEv
    fun:_ZN5blink12TextTrackCue17updateDisplayTreeEf
 }
 {
    bug_176619_b
    Memcheck:Uninitialized
    fun:_ZN5blink12WebVTTParser13collectDigitsERKN3WTF6StringEPj
    fun:_ZN5blink12WebVTTParser16collectTimeStampERKN3WTF6StringEPj
    fun:_ZN5blink12WebVTTParser22constructTreeFromTokenEPNS_8DocumentE
    fun:_ZN5blink12WebVTTParser33createDocumentFragmentFromCueTextERKN3WTF6StringE
    fun:_ZN5blink12TextTrackCue20createWebVTTNodeTreeEv
    fun:_ZN5blink12TextTrackCue22createCueRenderingTreeEv
    fun:_ZN5blink12TextTrackCue17updateDisplayTreeEf
 }
 {
-   bug_176621
-   Memcheck:Leak
-   fun:_Znw*
-   fun:_ZN13WebTestRunner10TestPlugin6createEPN5blink8WebFrameERKNS1_15WebPluginParamsEPNS_15WebTestDelegateE
-   fun:_ZN13WebTestRunner16WebTestProxyBase12createPluginEPN5blink8WebFrameERKNS1_15WebPluginParamsE
-   fun:_ZN13WebTestRunner12WebTestProxyI11WebViewHostP9TestShellE12createPluginEPN5blink8WebFrameERKNS5_15WebPluginParamsE
-   fun:_ZN5blink21FrameLoaderClientImpl12createPluginERKN7blink7IntSizeEPNS1_17HTMLPlugInElementERKNS1_4KURLERKN3WTF6VectorINSA_6String*
-   fun:_ZN5blink14SubframeLoader10loadPluginEPNS_22HTMLPlugInImageElementERKNS_4KURLERKN3WTF6StringERKNS6_6VectorIS7*
-}
-{
    bug_176891a
    Memcheck:Leak
    fun:calloc
    fun:nss_ZAlloc
    fun:nssCryptokiObject_Create
    fun:create_objects_from_handles
    fun:find_objects
    fun:find_objects_by_template
    fun:nssToken_FindCertificateByEncodedCertificate
    fun:PK11_FindCertFromDERCertItem
@@ skipping 314 matching lines @@
    fun:_ZN12SkBaseDevice10readPixelsE*
    fun:_ZN8SkCanvas10readPixelsE*
    fun:_ZN5blink15GraphicsContext10readPixelsE*
    ...
    fun:_ZN*blink24CanvasRenderingContext2D12getImageDataE*
    ...
    fun:_ZN5blink34CanvasRenderingContext2DV8InternalL18getImageDataMethodERKN2v820FunctionCallbackInfoINS1_5ValueEEE
    fun:_ZN5blink34CanvasRenderingContext2DV8InternalL26getImageDataMethodCallbackERKN2v820FunctionCallbackInfoINS1_5ValueEEE
 }
 {
-   bug_309477
-   Memcheck:Uninitialized
-   fun:_ZN13WebTestRunner11EventSender5resetEv
-   fun:_ZN13WebTestRunner14TestInterfaces26resetTestHelperControllersEv
-   fun:_ZN13WebTestRunner14TestInterfaces8resetAllEv
-   ...
-   fun:_ZN7content26ShellRenderProcessObserver17WebKitInitializedEv
-   fun:_ZN7content16RenderThreadImpl23EnsureWebKitInitializedEv
-   fun:_ZN7content16RenderThreadImpl15OnCreateNewViewERK18ViewMsg_New_Params
-}
-{
    bug_317166
    Memcheck:Leak
    fun:malloc
    fun:_dl_close_worker
    fun:_dl_close
    fun:_dl_catch_error
    fun:_dlerror_run
    fun:dlclose
    obj:/usr/lib/x86_64-linux-gnu/libasound.so.2.0.0
    fun:snd_config_searcha_hooks
@@ skipping 1173 matching lines @@
    ...
    fun:_ZN7content28ShellURLRequestContextGetter20GetURLRequestContextEv
    fun:_ZN7content21ChromeAppCacheService20InitializeOnIOThreadERKN4base8FilePathEPNS_15ResourceContextEPN3net23URLRequestContextGetterE13scoped_refptrIN7storage20SpecialStoragePolicyEE
 }
 {
    bug_587544_b
    Memcheck:Leak
    ...
    fun:_ZN4base4BindIMN7content21ChromeAppCacheServiceEFvRKNS_8FilePathEPNS1_15ResourceContextEPN3net23URLRequestContextGetterE13scoped_refptrIN7storage20SpecialStoragePolicyEEEJPS2_S3_S7_SB_IS9_ESE_EEENS_8CallbackINS_8internal22MakeUnboundRunTypeImplIT_JDpT0_EE4TypeEEESM_DpOSN_
 }