Return HALF_FLOAT as an implementation read type in ES3.

BUG=765953

Change-Id: I4dc79921766975cd75c489887b7e57ec4666fbbb
Reviewed-on: https://chromium-review.googlesource.com/685897
Reviewed-by: Zhenyao Mo <zmo@chromium.org>
Commit-Queue: Geoff Lang <geofflang@chromium.org>
diff --git a/src/libANGLE/formatutils.cpp b/src/libANGLE/formatutils.cpp
index faf985c..cf4a2fb 100644
--- a/src/libANGLE/formatutils.cpp
+++ b/src/libANGLE/formatutils.cpp
@@ -312,15 +312,24 @@
     return format;
 }
 
-GLenum InternalFormat::getReadPixelsType() const
+GLenum InternalFormat::getReadPixelsType(const Version &version) const
 {
     switch (type)
     {
         case GL_HALF_FLOAT:
-            // The internal format may have a type of GL_HALF_FLOAT but when exposing this type as
-            // the IMPLEMENTATION_READ_TYPE, only HALF_FLOAT_OES is allowed by
-            // OES_texture_half_float
-            return GL_HALF_FLOAT_OES;
+        case GL_HALF_FLOAT_OES:
+            if (version < Version(3, 0))
+            {
+                // The internal format may have a type of GL_HALF_FLOAT but when exposing this type
+                // as the IMPLEMENTATION_READ_TYPE, only HALF_FLOAT_OES is allowed by
+                // OES_texture_half_float.  HALF_FLOAT becomes core in ES3 and is acceptable to use
+                // as an IMPLEMENTATION_READ_TYPE.
+                return GL_HALF_FLOAT_OES;
+            }
+            else
+            {
+                return GL_HALF_FLOAT;
+            }
 
         default:
             return type;
diff --git a/src/libANGLE/formatutils.h b/src/libANGLE/formatutils.h
index 2d3f5f1..330afbd 100644
--- a/src/libANGLE/formatutils.h
+++ b/src/libANGLE/formatutils.h
@@ -83,7 +83,7 @@
 
     bool isLUMA() const;
     GLenum getReadPixelsFormat() const;
-    GLenum getReadPixelsType() const;
+    GLenum getReadPixelsType(const Version &version) const;
 
     // Return true if the format is a required renderbuffer format in the given version of the core
     // spec. Note that it isn't always clear whether all the rules that apply to core required
diff --git a/src/libANGLE/renderer/d3d/FramebufferD3D.cpp b/src/libANGLE/renderer/d3d/FramebufferD3D.cpp
index b7ce556..8fe577c 100644
--- a/src/libANGLE/renderer/d3d/FramebufferD3D.cpp
+++ b/src/libANGLE/renderer/d3d/FramebufferD3D.cpp
@@ -232,7 +232,7 @@
     const gl::InternalFormat &implementationFormatInfo =
         gl::GetSizedInternalFormatInfo(implementationFormat);
 
-    return implementationFormatInfo.getReadPixelsType();
+    return implementationFormatInfo.getReadPixelsType(context->getClientVersion());
 }
 
 gl::Error FramebufferD3D::readPixels(const gl::Context *context,
diff --git a/src/libANGLE/renderer/gl/FramebufferGL.cpp b/src/libANGLE/renderer/gl/FramebufferGL.cpp
index 1b30710..221af40 100644
--- a/src/libANGLE/renderer/gl/FramebufferGL.cpp
+++ b/src/libANGLE/renderer/gl/FramebufferGL.cpp
@@ -410,7 +410,7 @@
 {
     const auto *readAttachment = mState.getReadAttachment();
     const Format &format       = readAttachment->getFormat();
-    return format.info->getReadPixelsType();
+    return format.info->getReadPixelsType(context->getClientVersion());
 }
 
 Error FramebufferGL::readPixels(const gl::Context *context,
diff --git a/src/libANGLE/renderer/null/FramebufferNULL.cpp b/src/libANGLE/renderer/null/FramebufferNULL.cpp
index 0112623..39a7adc 100644
--- a/src/libANGLE/renderer/null/FramebufferNULL.cpp
+++ b/src/libANGLE/renderer/null/FramebufferNULL.cpp
@@ -109,7 +109,7 @@
 
     const gl::Format &format = readAttachment->getFormat();
     ASSERT(format.info != nullptr);
-    return format.info->getReadPixelsType();
+    return format.info->getReadPixelsType(context->getClientVersion());
 }
 
 gl::Error FramebufferNULL::readPixels(const gl::Context *context,