tests: reduce dependence on solvespace.h in order to reduce build time

Only include files that are actually needed, instead of using the huge
dependency that is `solvespace.h`.

Author: iscgar

test/analysis/contour_area/test.cpp

@@ -1,3 +1,5 @@
+#include "solvespace.h"
+
 #include "harness.h"
 
 TEST_CASE(normal_roundtrip) {

test/constraint/pt_on_circle/test.cpp

@@ -1,3 +1,5 @@
+#include "solvespace.h"
+
 #include "harness.h"
 
 TEST_CASE(normal_roundtrip) {

test/core/expr/test.cpp

@@ -1,3 +1,5 @@
+#include "expr.h"
+
 #include "harness.h"
 
 #define CHECK_PARSE(var, expr) \

test/core/locale/test.cpp

@@ -1,3 +1,5 @@
+#include "ui.h"
+
 #include "harness.h"
 
 TEST_CASE(parseable) {

test/group/translate_asy/test.cpp

@@ -1,3 +1,5 @@
+#include "solvespace.h"
+
 #include "harness.h"
 
 TEST_CASE(normal_roundtrip) {

test/harness.cpp

@@ -4,11 +4,14 @@
 // Copyright 2016 whitequark
 //-----------------------------------------------------------------------------
 #include <chrono>
+#include <cmath>
 #include <cstdio>
 #include <random>
 #include <regex>
 #include <cairo.h>
 
+#include "solvespace.h"
+
 #include "harness.h"
 
 #if defined(WIN32)
@@ -19,7 +22,7 @@
 
 namespace SolveSpace {
 namespace Platform {
-    // These are defined in headless.cpp, and aren't exposed in solvespace.h.
+    // These are defined in guinone.cpp, and aren't exposed in solvespace.h.
     extern std::vector<Platform::Path> fontFiles;
 }
 }

test/harness.h

@@ -3,7 +3,10 @@
 //
 // Copyright 2016 whitequark
 //-----------------------------------------------------------------------------
-#include "solvespace.h"
+#include <functional>
+#include <string>
+
+#include "platform/platform.h"
 
 // Hack... we should rename the ones in ui.h instead.
 #undef CHECK_TRUE

test/request/circle/test.cpp

@@ -1,3 +1,5 @@
+#include "solvespace.h"
+
 #include "harness.h"
 
 TEST_CASE(normal_roundtrip) {