Fix memory leak from use of SECKEY_ConvertToPublicKey().

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 # running overnight and removing outdated bugs/suppressions.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 6248 matching lines @@
    fun:_ZN7content11ContentMainEiPPKcPNS_19ContentMainDelegateE
 }
 {
    bug_347683
    Memcheck:Leak
    fun:_Znw*
    fun:_ZNK13LoginDatabase9GetLoginsERKN8autofill12PasswordFormEPSt6vectorIPS1_SaIS5_EE
    fun:_ZN50LoginDatabaseTest_UpdateIncompleteCredentials_Test8TestBodyEv
 }
 {
-   bug_347965
-   Memcheck:Leak
-   ...
-   fun:SECKEY_ConvertToPublicKey
-   fun:_ZN7content9webcrypto8platform12_GLOBAL__N_125CreatePrivateKeyAlgorithmERKN5blink18WebCryptoAlgorithmEP19SECKEYPrivateKeyStrPNS3_21WebCryptoKeyAlgorithmE
-   fun:_ZN7content9webcrypto8platform14ImportKeyPkcs8ERKN5blink18WebCryptoAlgorithmERKNS0_10CryptoDataEbiPNS2_12WebCryptoKeyE
-   fun:_ZN7content9webcrypto9ImportKeyEN5blink18WebCryptoKeyFormatERKNS0_10CryptoDataERKNS1_18WebCryptoAlgorithmEbiPNS1_12WebCryptoKeyE
-}
-{
    bug_347967_a
    Memcheck:Uninitialized
    fun:unpack_RGBA8888
    fun:_mesa_unpack_rgba_row
    fun:slow_read_rgba_pixels
    fun:read_rgba_pixels
    fun:_mesa_readpixels
    fun:_mesa_ReadnPixelsARB
    fun:_mesa_ReadPixels
    fun:shared_dispatch_stub_256
@@ skipping 17 matching lines @@
    fun:_mesa_CopyTexSubImage2D
    fun:shared_dispatch_stub_326
    fun:_ZN3gfx9GLApiBase21glCopyTexSubImage2DFnEjiiiiiii
    fun:_ZN3gpu5gles216GLES2DecoderImpl19DoCopyTexSubImage2DEjiiiiiii
    fun:_ZN3gpu5gles216GLES2DecoderImpl23HandleCopyTexSubImage2DEjRKNS0_4cmds17CopyTexSubImage2DE
    fun:_ZN3gpu5gles216GLES2DecoderImpl9DoCommandEjjPKv
    fun:_ZN3gpu13CommandParser14ProcessCommandEv
    fun:_ZN3gpu12GpuScheduler10PutChangedEv
    fun:_ZN3gpu22InProcessCommandBuffer12PumpCommandsEv
 }