Suppress leaks/uninitialized found in compositor_unittests

tools/heapcheck/suppressions.txt

 # There are three 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 # running overnight and removing outdated bugs/suppressions.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 187 matching lines @@
    fun:aura::RootWindowHost::Create
 }
 {
    bug_146464_c
    Heapcheck:Leak
    fun:??
    ...
    fun:RootWindowHostLinux
    fun:aura::RootWindowHost::Create
 }
+# leak in OSMesa used to run compositor_unittests in bots.
+{
+   bug_148477_a
+   Heapcheck:Leak
+   ...
+   fun:gfx::GLContextOSMesa::MakeCurrent
+   ...
+   fun:webkit::gpu::WebGraphicsContext3DInProcessImpl::*
+}
+{
+   bug_148477_b
+   Heapcheck:Leak
+   ...
+   fun:webkit::gpu::WebGraphicsContext3DInProcessImpl::compileShader
+   fun:WebCore::ProgramBindingBase::loadShader
+   fun:WebCore::ProgramBindingBase::init
+   fun:WebCore::ProgramBinding::ProgramBinding
+   ...
+   fun:WebCore::CCSingleThreadProxy::commitAndComposite
+   fun:WebCore::CCSingleThreadProxy::compositeImmediately
+   fun:WebCore::CCLayerTreeHost::composite
+   fun:WebKit::WebLayerTreeViewImpl::composite
+}
+{
+   bug_148477_c
+   Heapcheck:Leak
+   ...
+   fun:webkit::gpu::WebGraphicsContext3DInProcessImpl::linkProgram
+   fun:WebCore::ProgramBindingBase::link
+   fun:WebCore::ProgramBinding::initialize
+   ...
+   fun:WebCore::CCRendererGL::drawQuad
+   fun:WebCore::CCDirectRenderer::drawRenderPass
+   fun:WebCore::CCDirectRenderer::drawFrame
+   fun:WebCore::CCLayerTreeHostImpl::drawLayers
+   fun:WebCore::CCSingleThreadProxy::doComposite
+   fun:WebCore::CCSingleThreadProxy::commitAndComposite
+   fun:WebCore::CCSingleThreadProxy::compositeImmediately
+   fun:WebCore::CCLayerTreeHost::composite
+   fun:WebKit::WebLayerTreeViewImpl::composite
+   fun:ui::Compositor::Draw
+}
+
 
 #-----------------------------------------------------------------------
 # 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
 {
    Heapcheck sanity test (ToolsSanityTest.MemoryLeak).
    Heapcheck:Leak
    fun:base::ToolsSanityTest_MemoryLeak_Test::TestBody
 }
 {
@@ skipping 1354 matching lines @@
    fun:ash::Shell::InitRootWindowController
    fun:ash::Shell::Init
 }
 {
    bug_147756_b
    Heapcheck:Leak
    fun:ash::::CreateContainersInRootWindow
    fun:ash::internal::RootWindowController::CreateContainers
    fun:ash::Shell::Init
 }