Refactor Context dependency for resolveCompile

The context parameter of Shader::resolveCompile method causes a bad
impact that many methods in Shader, Program etc. have to have a same
context parameter. By removing it, these methods can be decoupled
from Context.

BUG=chromium:849576

Change-Id: Ia5545ee9dce45794550f6086bc0e6c4707e1276e
Reviewed-on: https://chromium-review.googlesource.com/1172202
Commit-Queue: Jie A Chen <jie.a.chen@intel.com>
Reviewed-by: Jamie Madill <jmadill@chromium.org>
diff --git a/src/libANGLE/renderer/null/ShaderNULL.cpp b/src/libANGLE/renderer/null/ShaderNULL.cpp
index 59ae007..4e3b9e7 100644
--- a/src/libANGLE/renderer/null/ShaderNULL.cpp
+++ b/src/libANGLE/renderer/null/ShaderNULL.cpp
@@ -30,14 +30,12 @@
     return 0;
 }
 
-bool ShaderNULL::postTranslateCompile(const gl::Context *context,
-                                      gl::Compiler *compiler,
-                                      std::string *infoLog)
+bool ShaderNULL::postTranslateCompile(gl::Compiler *compiler, std::string *infoLog)
 {
     return true;
 }
 
-std::string ShaderNULL::getDebugInfo(const gl::Context *context) const
+std::string ShaderNULL::getDebugInfo() const
 {
     return "";
 }