[GLESv3] Texture state tracking upgrades

- TextureUtils to get the low down on all offset/size related calculations
(ripped from SwiftShader)
    - This involves track of all PBO fields
- Move TextureRec and friends to GLSharedGroup
- Implement new encoder utils to use in encoder

Change-Id: Ic6585f49d2928fe965181ec706d5fefa8713e0eb
diff --git a/shared/OpenglCodecCommon/GLSharedGroup.cpp b/shared/OpenglCodecCommon/GLSharedGroup.cpp
index 3b5211f..1b8facf 100755
--- a/shared/OpenglCodecCommon/GLSharedGroup.cpp
+++ b/shared/OpenglCodecCommon/GLSharedGroup.cpp
@@ -252,6 +252,10 @@
     return m_buffers.valueFor(bufferId);
 }
 
+SharedTextureDataMap* GLSharedGroup::getTextureData() {
+    return &m_textureRecs;
+}
+
 void GLSharedGroup::addBufferData(GLuint bufferId, GLsizeiptr size, void * data)
 {
     android::AutoMutex _lock(m_lock);