Fix memory-handling issues in the OpenGL code.

This fixes the folloiwng cppcheck reports:
[device/generic/goldfish/opengl/system/GLESv2_enc/GL2Encoder.cpp:789]:
  (error) Mismatching allocation and deallocation: str
[device/generic/goldfish/opengl/system/GLESv2_enc/GL2Encoder.cpp:795]:
  (error) Mismatching allocation and deallocation: str
[device/generic/goldfish/opengl/tests/gles_android_wrapper/egl.cpp:492]:
  (error) Mismatching allocation and deallocation: attrib

Change-Id: Iaf494eca1b927b2fa4b91f01ba340746b9da9bd3
(cherry picked from commit 3375e5e21450b78daf109225707d574976b7ec1c)
diff --git a/system/GLESv2_enc/GL2Encoder.cpp b/system/GLESv2_enc/GL2Encoder.cpp
index 853a6a7..119500d 100755
--- a/system/GLESv2_enc/GL2Encoder.cpp
+++ b/system/GLESv2_enc/GL2Encoder.cpp
@@ -803,13 +803,13 @@
     // Perhaps we can borrow Mesa's pre-processor?
 
     if (!replaceSamplerExternalWith2D(str, shaderData)) {
-        delete str;
+        delete[] str;
         ctx->setError(GL_OUT_OF_MEMORY);
         return;
     }
 
     ctx->glShaderString(ctx, shader, str, len + 1);
-    delete str;
+    delete[] str;
 }
 
 void GL2Encoder::s_glFinish(void *self)