The default uniform descriptor set is reset while recreating the
pipeline layout during handling of immutable samplers and then is
never re-allocated and bound before the next draw.

The call stack to allocate the program uniforms descriptor set:

    ProgramExecutableVk::allocUniformAndXfbDescriptorSet
    ProgramVk::updateUniforms
    ContextVk::setupDraw
    ContextVk::drawArrays
    Context::drawArrays

Unfortunately, this occurs before the pipeline layout is reset (and the
descriptor sets are reset) due to the presence of an immutable sampler:

    ProgramExecutableVk::reset <<---- mDescriptorSets.fill(VK_NULL_HANDLE);
    ProgramExecutableVk::createPipelineLayout
    ContextVk::updateActiveTextures
    ContextVk::invalidateCurrentTextures
    ContextVk::syncState
    Context::syncDirtyBits
    Context::prepareForDraw
    Context::drawArrays

This CL calls setAllDefaultUniformsDirty() for the Program/PPO to ensure
the default uniforms descriptor sets are re-allocated and re-bound
before the next draw command.

Bug: b/178424566
Bug: angleproject:5624
Test: CtsCameraTestCases
Change-Id: If54a9f2cc09809a5103bc3eac641c77f56362229
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2677385Reviewed-by: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org>
Commit-Queue: Tim Van Patten <timvp@google.com>