Fix rendering issue in Tegra2/3.

Now having medium precision for specular variable, so that specular power can be <1.0

Change-Id: I15459d34e269ba7d31bc899460540fe390e5e294
diff --git a/ndk/platforms/android-17/samples/Teapot/assets/Shaders/ShaderPlain.fsh b/ndk/platforms/android-17/samples/Teapot/assets/Shaders/ShaderPlain.fsh
index 1725138..693e4fc 100644
--- a/ndk/platforms/android-17/samples/Teapot/assets/Shaders/ShaderPlain.fsh
+++ b/ndk/platforms/android-17/samples/Teapot/assets/Shaders/ShaderPlain.fsh
@@ -5,7 +5,7 @@
 #define USE_PHONG (1)
 
 uniform lowp vec3       vMaterialAmbient;
-uniform lowp vec4       vMaterialSpecular;
+uniform mediump vec4       vMaterialSpecular;
 
 varying lowp vec4 colorDiffuse;
 
diff --git a/ndk/platforms/android-18/samples/MoreTeapots/assets/Shaders/ShaderPlain.fsh b/ndk/platforms/android-18/samples/MoreTeapots/assets/Shaders/ShaderPlain.fsh
index cf52e9d..9f97be8 100644
--- a/ndk/platforms/android-18/samples/MoreTeapots/assets/Shaders/ShaderPlain.fsh
+++ b/ndk/platforms/android-18/samples/MoreTeapots/assets/Shaders/ShaderPlain.fsh
@@ -3,7 +3,7 @@
 //
 
 uniform lowp vec3       vMaterialAmbient;
-uniform lowp vec4       vMaterialSpecular;
+uniform mediump vec4       vMaterialSpecular;
 
 varying lowp vec4 colorDiffuse;
 
diff --git a/ndk/platforms/android-18/samples/MoreTeapots/assets/Shaders/ShaderPlainES3.fsh b/ndk/platforms/android-18/samples/MoreTeapots/assets/Shaders/ShaderPlainES3.fsh
index e9fefc9..440c90d 100644
--- a/ndk/platforms/android-18/samples/MoreTeapots/assets/Shaders/ShaderPlainES3.fsh
+++ b/ndk/platforms/android-18/samples/MoreTeapots/assets/Shaders/ShaderPlainES3.fsh
@@ -1,7 +1,7 @@
 #version 300 es
 precision mediump float;
 
-uniform lowp vec4  vMaterialSpecular;
+uniform mediump vec4  vMaterialSpecular;
 uniform highp vec3 vLight0;
 
 in lowp vec4 colorDiffuse;