Add config options to run different GPU APIs to dm and nanobench

Add extended config specification form that can be used to run different
gpu backend with different APIs.

The configs can be specified with the form:
gpu(api=string,dit=bool,nvpr=bool,samples=int)

This replaces and removes the --gpuAPI flag.

All existing configs should still work.

Adds following documentation:

out/Debug/dm --help config

Flags:
    --config:	type: string	default: 565 8888 gpu nonrendering
        Options: 565 8888 debug gpu gpudebug gpudft gpunull msaa16 msaa4
        nonrendering null nullgpu nvprmsaa16 nvprmsaa4 pdf pdf_poppler skp svg
        xps or use extended form 'backend(option=value,...)'.

        Extended form: 'backend(option=value,...)'

        Possible backends and options:

        gpu(api=string,dit=bool,nvpr=bool,samples=int)	GPU backend
        	api	type: string	default: native.
        	    Select graphics API to use with gpu backend.
        	    Options:
        		native			Use platform default OpenGL or OpenGL ES backend.
        		gl    			Use OpenGL.
        		gles  			Use OpenGL ES.
        		debug 			Use debug OpenGL.
        		null  			Use null OpenGL.
        	dit	type: bool	default: false.
        	    Use device independent text.
        	nvpr	type: bool	default: false.
        	    Use NV_path_rendering OpenGL and OpenGL ES extension.
        	samples	type: int	default: 0.
        	    Use multisampling with N samples.

        Predefined configs:

        	gpu      	= gpu()
        	msaa4    	= gpu(samples=4)
        	msaa16   	= gpu(samples=16)
        	nvprmsaa4	= gpu(nvpr=true,samples=4)
        	nvprmsaa16	= gpu(nvpr=true,samples=16)
        	gpudft    	= gpu(dit=true)
        	gpudebug  	= gpu(api=debug)
        	gpunull   	= gpu(api=null)
        	debug     	= gpu(api=debug)
        	nullgpu   	= gpu(api=null)

BUG=skia:2992

Committed: https://skia.googlesource.com/skia/+/e13ca329fca4c28cf4e078561f591ab27b743d23
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1490113005

Review URL: https://codereview.chromium.org/1490113005

7 files changed, 76 insertions, 47 deletions

diff --git a/src/core/SkString.cpp b/src/core/SkString.cpp
index d93f662da3..b5655e0503 100644
--- a/src/core/SkString.cpp
+++ b/src/core/SkString.cpp
@@ -624,16 +624,35 @@ SkString SkStringPrintf(const char* format, ...) {
     return formattedOutput;
 }
 
-void SkStrSplit(const char* str, const char* delimiters, SkTArray<SkString>* out) {
-    const char* end = str + strlen(str);
-    while (str != end) {
-        // Find a token.
-        const size_t len = strcspn(str, delimiters);
-        out->push_back().set(str, len);
-        str += len;
+void SkStrSplit(const char* str, const char* delimiters, SkStrSplitMode splitMode,
+                SkTArray<SkString>* out) {
+    if (splitMode == kCoalesce_SkStrSplitMode) {
         // Skip any delimiters.
         str += strspn(str, delimiters);
     }
+    if (!*str) {
+        return;
+    }
+
+    while (true) {
+        // Find a token.
+        const size_t len = strcspn(str, delimiters);
+        if (splitMode == kStrict_SkStrSplitMode || len > 0) {
+            out->push_back().set(str, len);
+            str += len;
+        }
+
+        if (!*str) {
+            return;
+        }
+        if (splitMode == kCoalesce_SkStrSplitMode) {
+            // Skip any delimiters.
+            str += strspn(str, delimiters);
+        } else {
+            // Skip one delimiter.
+            str += 1;
+        }
+    }
 }
 
 #undef VSNPRINTF
diff --git a/src/gpu/GrContextFactory.cpp b/src/gpu/GrContextFactory.cpp
index 15af8162b1..4814e7870e 100755
--- a/src/gpu/GrContextFactory.cpp
+++ b/src/gpu/GrContextFactory.cpp
@@ -24,13 +24,10 @@
 #include "GrCaps.h"
 
 GrContextFactory::ContextInfo* GrContextFactory::getContextInfo(GLContextType type,
-                                                                GrGLStandard forcedGpuAPI,
                                                                 GLContextOptions options) {
     for (int i = 0; i < fContexts.count(); ++i) {
         if (fContexts[i]->fType == type &&
-            fContexts[i]->fOptions == options &&
-            (forcedGpuAPI == kNone_GrGLStandard ||
-             forcedGpuAPI == fContexts[i]->fGLContext->gl()->fStandard)) {
+            fContexts[i]->fOptions == options) {
             fContexts[i]->fGLContext->makeCurrent();
             return fContexts[i];
         }
@@ -39,31 +36,39 @@ GrContextFactory::ContextInfo* GrContextFactory::getContextInfo(GLContextType ty
     SkAutoTUnref<GrContext> grCtx;
     switch (type) {
         case kNative_GLContextType:
-            glCtx.reset(SkCreatePlatformGLContext(forcedGpuAPI));
+            glCtx.reset(SkCreatePlatformGLContext(kNone_GrGLStandard));
             break;
-#ifdef SK_ANGLE
+        case kGL_GLContextType:
+            glCtx.reset(SkCreatePlatformGLContext(kGL_GrGLStandard));
+            break;
+        case kGLES_GLContextType:
+            glCtx.reset(SkCreatePlatformGLContext(kGLES_GrGLStandard));
+            break;
+#if SK_ANGLE
+#ifdef SK_BUILD_FOR_WIN
         case kANGLE_GLContextType:
-            glCtx.reset(SkANGLEGLContext::Create(forcedGpuAPI, false));
+            glCtx.reset(SkANGLEGLContext::CreateDirectX());
             break;
+#endif
         case kANGLE_GL_GLContextType:
-            glCtx.reset(SkANGLEGLContext::Create(forcedGpuAPI, true));
+            glCtx.reset(SkANGLEGLContext::CreateOpenGL());
             break;
 #endif
-#ifdef SK_COMMAND_BUFFER
+#if SK_COMMAND_BUFFER
         case kCommandBuffer_GLContextType:
-            glCtx.reset(SkCommandBufferGLContext::Create(forcedGpuAPI));
+            glCtx.reset(SkCommandBufferGLContext::Create());
             break;
 #endif
-#ifdef SK_MESA
+#if SK_MESA
         case kMESA_GLContextType:
-            glCtx.reset(SkMesaGLContext::Create(forcedGpuAPI));
+            glCtx.reset(SkMesaGLContext::Create());
             break;
 #endif
         case kNull_GLContextType:
-            glCtx.reset(SkNullGLContext::Create(forcedGpuAPI));
+            glCtx.reset(SkNullGLContext::Create());
             break;
         case kDebug_GLContextType:
-            glCtx.reset(SkDebugGLContext::Create(forcedGpuAPI));
+            glCtx.reset(SkDebugGLContext::Create());
             break;
     }
     if (nullptr == glCtx.get()) {
diff --git a/src/gpu/GrContextFactory.h b/src/gpu/GrContextFactory.h
index 5097813817..1df99d6ff1 100644
--- a/src/gpu/GrContextFactory.h
+++ b/src/gpu/GrContextFactory.h
@@ -24,19 +24,23 @@
 class GrContextFactory : SkNoncopyable {
 public:
     enum GLContextType {
-        kNative_GLContextType,
+        kNative_GLContextType,  //! OpenGL or OpenGL ES context.
+        kGL_GLContextType,      //! OpenGL context.
+        kGLES_GLContextType,    //! OpenGL ES context.
 #if SK_ANGLE
-        kANGLE_GLContextType,
-        kANGLE_GL_GLContextType,
+#ifdef SK_BUILD_FOR_WIN
+        kANGLE_GLContextType,    //! ANGLE on DirectX OpenGL ES context.
+#endif
+        kANGLE_GL_GLContextType, //! ANGLE on OpenGL OpenGL ES context.
 #endif
 #if SK_COMMAND_BUFFER
-        kCommandBuffer_GLContextType,
+        kCommandBuffer_GLContextType, //! Chromium command buffer OpenGL ES context.
 #endif
 #if SK_MESA
-        kMESA_GLContextType,
+        kMESA_GLContextType,  //! MESA OpenGL context
 #endif
-        kNull_GLContextType,
-        kDebug_GLContextType,
+        kNull_GLContextType,  //! Non-rendering OpenGL mock context.
+        kDebug_GLContextType, //! Non-rendering, state verifying OpenGL context.
         kLastGLContextType = kDebug_GLContextType
     };
 
@@ -65,11 +69,15 @@ public:
         switch (type) {
             case kNative_GLContextType:
                 return "native";
-            case kNull_GLContextType:
-                return "null";
+            case kGL_GLContextType:
+                return "gl";
+            case kGLES_GLContextType:
+                return "gles";
 #if SK_ANGLE
+#ifdef SK_BUILD_FOR_WIN
             case kANGLE_GLContextType:
                 return "angle";
+#endif
             case kANGLE_GL_GLContextType:
                 return "angle-gl";
 #endif
@@ -81,6 +89,8 @@ public:
             case kMESA_GLContextType:
                 return "mesa";
 #endif
+            case kNull_GLContextType:
+                return "null";
             case kDebug_GLContextType:
                 return "debug";
             default:
@@ -124,15 +134,14 @@ public:
      * Get a context initialized with a type of GL context. It also makes the GL context current.
      * Pointer is valid until destroyContexts() is called.
      */
-    ContextInfo* getContextInfo(GLContextType type, GrGLStandard forcedGpuAPI = kNone_GrGLStandard,
+    ContextInfo* getContextInfo(GLContextType type,
                                 GLContextOptions options = kNone_GLContextOptions);
 
     /**
      * Get a GrContext initialized with a type of GL context. It also makes the GL context current.
      */
-    GrContext* get(GLContextType type, GrGLStandard forcedGpuAPI = kNone_GrGLStandard,
-                   GLContextOptions options = kNone_GLContextOptions) {
-        if (ContextInfo* info = this->getContextInfo(type, forcedGpuAPI, options)) {
+    GrContext* get(GLContextType type, GLContextOptions options = kNone_GLContextOptions) {
+        if (ContextInfo* info = this->getContextInfo(type, options)) {
             return info->fGrContext;
         }
         return nullptr;
diff --git a/src/gpu/gl/SkNullGLContext.cpp b/src/gpu/gl/SkNullGLContext.cpp
index e7270c32c4..dafa1ef0bc 100644
--- a/src/gpu/gl/SkNullGLContext.cpp
+++ b/src/gpu/gl/SkNullGLContext.cpp
@@ -578,10 +578,7 @@ static void set_current_context_from_interface(const GrGLInterface* interface) {
 }
 #endif
 
-SkNullGLContext* SkNullGLContext::Create(GrGLStandard forcedGpuAPI) {
-    if (kGLES_GrGLStandard == forcedGpuAPI) {
-        return nullptr;
-    }
+SkNullGLContext* SkNullGLContext::Create() {
     SkNullGLContext* ctx = new SkNullGLContext;
     if (!ctx->isValid()) {
         delete ctx;
diff --git a/src/gpu/gl/angle/SkANGLEGLContext.cpp b/src/gpu/gl/angle/SkANGLEGLContext.cpp
index 54ef02d492..2c9f38e1d9 100644
--- a/src/gpu/gl/angle/SkANGLEGLContext.cpp
+++ b/src/gpu/gl/angle/SkANGLEGLContext.cpp
@@ -180,7 +180,12 @@ GrGLuint SkANGLEGLContext::eglImageToExternalTexture(GrEGLImage image) const {
 }
 
 SkGLContext* SkANGLEGLContext::createNew() const {
-    SkGLContext* ctx = SkANGLEGLContext::Create(this->gl()->fStandard, fIsGLBackend);
+#ifdef SK_BUILD_FOR_WIN
+    SkGLContext* ctx = fIsGLBackend ? SkANGLEGLContext::CreateOpenGL()
+                                    : SkANGLEGLContext::CreateDirectX();
+#else
+    SkGLContext* ctx = SkANGLEGLContext::CreateOpenGL();
+#endif
     if (ctx) {
         ctx->makeCurrent();
     }
diff --git a/src/gpu/gl/debug/SkDebugGLContext.h b/src/gpu/gl/debug/SkDebugGLContext.h
index abbcf559c5..113a254e0b 100644
--- a/src/gpu/gl/debug/SkDebugGLContext.h
+++ b/src/gpu/gl/debug/SkDebugGLContext.h
@@ -14,10 +14,7 @@ class SkDebugGLContext : public SkGLContext {
 public:
     ~SkDebugGLContext() override;
 
-    static SkDebugGLContext* Create(GrGLStandard forcedGpuAPI) {
-        if (kGLES_GrGLStandard == forcedGpuAPI) {
-            return nullptr;
-        }
+    static SkDebugGLContext* Create() {
         return new SkDebugGLContext;
     }
 private:
diff --git a/src/gpu/gl/mesa/SkMesaGLContext.h b/src/gpu/gl/mesa/SkMesaGLContext.h
index a58f1c890e..a9c77a81da 100644
--- a/src/gpu/gl/mesa/SkMesaGLContext.h
+++ b/src/gpu/gl/mesa/SkMesaGLContext.h
@@ -19,10 +19,7 @@ private:
 public:
     ~SkMesaGLContext() override;
 
-    static SkMesaGLContext* Create(GrGLStandard forcedGpuAPI) {
-        if (kGLES_GrGLStandard == forcedGpuAPI) {
-            return nullptr;
-        }
+    static SkMesaGLContext* Create() {
         SkMesaGLContext* ctx = new SkMesaGLContext;
         if (!ctx->isValid()) {
             delete ctx;